diff --git a/frontend/package-lock.json b/frontend/package-lock.json
index b1ea2966..b33bbcd5 100644
--- a/frontend/package-lock.json
+++ b/frontend/package-lock.json
@@ -31,6 +31,7 @@
 				"@types/diff": "^7.0.2",
 				"@types/node": "^24",
 				"@vitest/browser-playwright": "^4.0.10",
+				"@vitest/coverage-istanbul": "^4.1.0",
 				"@vitest/coverage-v8": "^4.1.0",
 				"eslint": "^9.39.1",
 				"eslint-config-prettier": "^10.1.8",
@@ -129,6 +130,153 @@
 				"node": ">=6.9.0"
 			}
 		},
+		"node_modules/@babel/compat-data": {
+			"version": "7.29.3",
+			"resolved": "https://registry.npmjs.org/@babel/compat-data/-/compat-data-7.29.3.tgz",
+			"integrity": "sha512-LIVqM46zQWZhj17qA8wb4nW/ixr2y1Nw+r1etiAWgRM6U1IqP+LNhL1yg440jYZR72jCWcWbLWzIosH+uP1fqg==",
+			"dev": true,
+			"license": "MIT",
+			"engines": {
+				"node": ">=6.9.0"
+			}
+		},
+		"node_modules/@babel/core": {
+			"version": "7.29.0",
+			"resolved": "https://registry.npmjs.org/@babel/core/-/core-7.29.0.tgz",
+			"integrity": "sha512-CGOfOJqWjg2qW/Mb6zNsDm+u5vFQ8DxXfbM09z69p5Z6+mE1ikP2jUXw+j42Pf1XTYED2Rni5f95npYeuwMDQA==",
+			"dev": true,
+			"license": "MIT",
+			"dependencies": {
+				"@babel/code-frame": "^7.29.0",
+				"@babel/generator": "^7.29.0",
+				"@babel/helper-compilation-targets": "^7.28.6",
+				"@babel/helper-module-transforms": "^7.28.6",
+				"@babel/helpers": "^7.28.6",
+				"@babel/parser": "^7.29.0",
+				"@babel/template": "^7.28.6",
+				"@babel/traverse": "^7.29.0",
+				"@babel/types": "^7.29.0",
+				"@jridgewell/remapping": "^2.3.5",
+				"convert-source-map": "^2.0.0",
+				"debug": "^4.1.0",
+				"gensync": "^1.0.0-beta.2",
+				"json5": "^2.2.3",
+				"semver": "^6.3.1"
+			},
+			"engines": {
+				"node": ">=6.9.0"
+			},
+			"funding": {
+				"type": "opencollective",
+				"url": "https://opencollective.com/babel"
+			}
+		},
+		"node_modules/@babel/core/node_modules/semver": {
+			"version": "6.3.1",
+			"resolved": "https://registry.npmjs.org/semver/-/semver-6.3.1.tgz",
+			"integrity": "sha512-BR7VvDCVHO+q2xBEWskxS6DJE1qRnb7DxzUrogb71CWoSficBxYsiAGd+Kl0mmq/MprG9yArRkyrQxTO6XjMzA==",
+			"dev": true,
+			"license": "ISC",
+			"bin": {
+				"semver": "bin/semver.js"
+			}
+		},
+		"node_modules/@babel/generator": {
+			"version": "7.29.1",
+			"resolved": "https://registry.npmjs.org/@babel/generator/-/generator-7.29.1.tgz",
+			"integrity": "sha512-qsaF+9Qcm2Qv8SRIMMscAvG4O3lJ0F1GuMo5HR/Bp02LopNgnZBC/EkbevHFeGs4ls/oPz9v+Bsmzbkbe+0dUw==",
+			"dev": true,
+			"license": "MIT",
+			"dependencies": {
+				"@babel/parser": "^7.29.0",
+				"@babel/types": "^7.29.0",
+				"@jridgewell/gen-mapping": "^0.3.12",
+				"@jridgewell/trace-mapping": "^0.3.28",
+				"jsesc": "^3.0.2"
+			},
+			"engines": {
+				"node": ">=6.9.0"
+			}
+		},
+		"node_modules/@babel/helper-compilation-targets": {
+			"version": "7.28.6",
+			"resolved": "https://registry.npmjs.org/@babel/helper-compilation-targets/-/helper-compilation-targets-7.28.6.tgz",
+			"integrity": "sha512-JYtls3hqi15fcx5GaSNL7SCTJ2MNmjrkHXg4FSpOA/grxK8KwyZ5bubHsCq8FXCkua6xhuaaBit+3b7+VZRfcA==",
+			"dev": true,
+			"license": "MIT",
+			"dependencies": {
+				"@babel/compat-data": "^7.28.6",
+				"@babel/helper-validator-option": "^7.27.1",
+				"browserslist": "^4.24.0",
+				"lru-cache": "^5.1.1",
+				"semver": "^6.3.1"
+			},
+			"engines": {
+				"node": ">=6.9.0"
+			}
+		},
+		"node_modules/@babel/helper-compilation-targets/node_modules/lru-cache": {
+			"version": "5.1.1",
+			"resolved": "https://registry.npmjs.org/lru-cache/-/lru-cache-5.1.1.tgz",
+			"integrity": "sha512-KpNARQA3Iwv+jTA0utUVVbrh+Jlrr1Fv0e56GGzAFOXN7dk/FviaDW8LHmK52DlcH4WP2n6gI8vN1aesBFgo9w==",
+			"dev": true,
+			"license": "ISC",
+			"dependencies": {
+				"yallist": "^3.0.2"
+			}
+		},
+		"node_modules/@babel/helper-compilation-targets/node_modules/semver": {
+			"version": "6.3.1",
+			"resolved": "https://registry.npmjs.org/semver/-/semver-6.3.1.tgz",
+			"integrity": "sha512-BR7VvDCVHO+q2xBEWskxS6DJE1qRnb7DxzUrogb71CWoSficBxYsiAGd+Kl0mmq/MprG9yArRkyrQxTO6XjMzA==",
+			"dev": true,
+			"license": "ISC",
+			"bin": {
+				"semver": "bin/semver.js"
+			}
+		},
+		"node_modules/@babel/helper-globals": {
+			"version": "7.28.0",
+			"resolved": "https://registry.npmjs.org/@babel/helper-globals/-/helper-globals-7.28.0.tgz",
+			"integrity": "sha512-+W6cISkXFa1jXsDEdYA8HeevQT/FULhxzR99pxphltZcVaugps53THCeiWA8SguxxpSp3gKPiuYfSWopkLQ4hw==",
+			"dev": true,
+			"license": "MIT",
+			"engines": {
+				"node": ">=6.9.0"
+			}
+		},
+		"node_modules/@babel/helper-module-imports": {
+			"version": "7.28.6",
+			"resolved": "https://registry.npmjs.org/@babel/helper-module-imports/-/helper-module-imports-7.28.6.tgz",
+			"integrity": "sha512-l5XkZK7r7wa9LucGw9LwZyyCUscb4x37JWTPz7swwFE/0FMQAGpiWUZn8u9DzkSBWEcK25jmvubfpw2dnAMdbw==",
+			"dev": true,
+			"license": "MIT",
+			"dependencies": {
+				"@babel/traverse": "^7.28.6",
+				"@babel/types": "^7.28.6"
+			},
+			"engines": {
+				"node": ">=6.9.0"
+			}
+		},
+		"node_modules/@babel/helper-module-transforms": {
+			"version": "7.28.6",
+			"resolved": "https://registry.npmjs.org/@babel/helper-module-transforms/-/helper-module-transforms-7.28.6.tgz",
+			"integrity": "sha512-67oXFAYr2cDLDVGLXTEABjdBJZ6drElUSI7WKp70NrpyISso3plG9SAGEF6y7zbha/wOzUByWWTJvEDVNIUGcA==",
+			"dev": true,
+			"license": "MIT",
+			"dependencies": {
+				"@babel/helper-module-imports": "^7.28.6",
+				"@babel/helper-validator-identifier": "^7.28.5",
+				"@babel/traverse": "^7.28.6"
+			},
+			"engines": {
+				"node": ">=6.9.0"
+			},
+			"peerDependencies": {
+				"@babel/core": "^7.0.0"
+			}
+		},
 		"node_modules/@babel/helper-string-parser": {
 			"version": "7.27.1",
 			"resolved": "https://registry.npmjs.org/@babel/helper-string-parser/-/helper-string-parser-7.27.1.tgz",
@@ -149,6 +297,30 @@
 				"node": ">=6.9.0"
 			}
 		},
+		"node_modules/@babel/helper-validator-option": {
+			"version": "7.27.1",
+			"resolved": "https://registry.npmjs.org/@babel/helper-validator-option/-/helper-validator-option-7.27.1.tgz",
+			"integrity": "sha512-YvjJow9FxbhFFKDSuFnVCe2WxXk1zWc22fFePVNEaWJEu8IrZVlda6N0uHwzZrUM1il7NC9Mlp4MaJYbYd9JSg==",
+			"dev": true,
+			"license": "MIT",
+			"engines": {
+				"node": ">=6.9.0"
+			}
+		},
+		"node_modules/@babel/helpers": {
+			"version": "7.29.2",
+			"resolved": "https://registry.npmjs.org/@babel/helpers/-/helpers-7.29.2.tgz",
+			"integrity": "sha512-HoGuUs4sCZNezVEKdVcwqmZN8GoHirLUcLaYVNBK2J0DadGtdcqgr3BCbvH8+XUo4NGjNl3VOtSjEKNzqfFgKw==",
+			"dev": true,
+			"license": "MIT",
+			"dependencies": {
+				"@babel/template": "^7.28.6",
+				"@babel/types": "^7.29.0"
+			},
+			"engines": {
+				"node": ">=6.9.0"
+			}
+		},
 		"node_modules/@babel/parser": {
 			"version": "7.29.2",
 			"resolved": "https://registry.npmjs.org/@babel/parser/-/parser-7.29.2.tgz",
@@ -165,6 +337,40 @@
 				"node": ">=6.0.0"
 			}
 		},
+		"node_modules/@babel/template": {
+			"version": "7.28.6",
+			"resolved": "https://registry.npmjs.org/@babel/template/-/template-7.28.6.tgz",
+			"integrity": "sha512-YA6Ma2KsCdGb+WC6UpBVFJGXL58MDA6oyONbjyF/+5sBgxY/dwkhLogbMT2GXXyU84/IhRw/2D1Os1B/giz+BQ==",
+			"dev": true,
+			"license": "MIT",
+			"dependencies": {
+				"@babel/code-frame": "^7.28.6",
+				"@babel/parser": "^7.28.6",
+				"@babel/types": "^7.28.6"
+			},
+			"engines": {
+				"node": ">=6.9.0"
+			}
+		},
+		"node_modules/@babel/traverse": {
+			"version": "7.29.0",
+			"resolved": "https://registry.npmjs.org/@babel/traverse/-/traverse-7.29.0.tgz",
+			"integrity": "sha512-4HPiQr0X7+waHfyXPZpWPfWL/J7dcN1mx9gL6WdQVMbPnF3+ZhSMs8tCxN7oHddJE9fhNE7+lxdnlyemKfJRuA==",
+			"dev": true,
+			"license": "MIT",
+			"dependencies": {
+				"@babel/code-frame": "^7.29.0",
+				"@babel/generator": "^7.29.0",
+				"@babel/helper-globals": "^7.28.0",
+				"@babel/parser": "^7.29.0",
+				"@babel/template": "^7.28.6",
+				"@babel/types": "^7.29.0",
+				"debug": "^4.3.1"
+			},
+			"engines": {
+				"node": ">=6.9.0"
+			}
+		},
 		"node_modules/@babel/types": {
 			"version": "7.29.0",
 			"resolved": "https://registry.npmjs.org/@babel/types/-/types-7.29.0.tgz",
@@ -1128,6 +1334,16 @@
 				"node": ">=18.0.0"
 			}
 		},
+		"node_modules/@istanbuljs/schema": {
+			"version": "0.1.6",
+			"resolved": "https://registry.npmjs.org/@istanbuljs/schema/-/schema-0.1.6.tgz",
+			"integrity": "sha512-+Sg6GCR/wy1oSmQDFq4LQDAhm3ETKnorxN+y5nbLULOR3P0c14f2Wurzj3/xqPXtasLFfHd5iRFQ7AJt4KH2cw==",
+			"dev": true,
+			"license": "MIT",
+			"engines": {
+				"node": ">=8"
+			}
+		},
 		"node_modules/@jridgewell/gen-mapping": {
 			"version": "0.3.13",
 			"resolved": "https://registry.npmjs.org/@jridgewell/gen-mapping/-/gen-mapping-0.3.13.tgz",
@@ -3544,6 +3760,31 @@
 				}
 			}
 		},
+		"node_modules/@vitest/coverage-istanbul": {
+			"version": "4.1.0",
+			"resolved": "https://registry.npmjs.org/@vitest/coverage-istanbul/-/coverage-istanbul-4.1.0.tgz",
+			"integrity": "sha512-0+67gA94YToxd+Pc3XgIA/2c8HN2hXNSg3T+1FI4HW7W/2gPitYCtktsY6Ke7vrt5caboMq3TUf0/vwbHRb0og==",
+			"dev": true,
+			"license": "MIT",
+			"dependencies": {
+				"@babel/core": "^7.29.0",
+				"@istanbuljs/schema": "^0.1.3",
+				"@jridgewell/gen-mapping": "^0.3.13",
+				"@jridgewell/trace-mapping": "0.3.31",
+				"istanbul-lib-coverage": "^3.2.2",
+				"istanbul-lib-report": "^3.0.1",
+				"istanbul-reports": "^3.2.0",
+				"magicast": "^0.5.2",
+				"obug": "^2.1.1",
+				"tinyrainbow": "^3.0.3"
+			},
+			"funding": {
+				"url": "https://opencollective.com/vitest"
+			},
+			"peerDependencies": {
+				"vitest": "4.1.0"
+			}
+		},
 		"node_modules/@vitest/coverage-v8": {
 			"version": "4.1.0",
 			"resolved": "https://registry.npmjs.org/@vitest/coverage-v8/-/coverage-v8-4.1.0.tgz",
@@ -3864,6 +4105,19 @@
 			"dev": true,
 			"license": "MIT"
 		},
+		"node_modules/baseline-browser-mapping": {
+			"version": "2.10.29",
+			"resolved": "https://registry.npmjs.org/baseline-browser-mapping/-/baseline-browser-mapping-2.10.29.tgz",
+			"integrity": "sha512-Asa2krT+XTPZINCS+2QcyS8WTkObE77RwkydwF7h6DmnKqbvlalz93m/dnphUyCa6SWSP51VgtEUf2FN+gelFQ==",
+			"dev": true,
+			"license": "Apache-2.0",
+			"bin": {
+				"baseline-browser-mapping": "dist/cli.cjs"
+			},
+			"engines": {
+				"node": ">=6.0.0"
+			}
+		},
 		"node_modules/bidi-js": {
 			"version": "1.0.3",
 			"resolved": "https://registry.npmjs.org/bidi-js/-/bidi-js-1.0.3.tgz",
@@ -3897,6 +4151,40 @@
 				"node": ">=8"
 			}
 		},
+		"node_modules/browserslist": {
+			"version": "4.28.2",
+			"resolved": "https://registry.npmjs.org/browserslist/-/browserslist-4.28.2.tgz",
+			"integrity": "sha512-48xSriZYYg+8qXna9kwqjIVzuQxi+KYWp2+5nCYnYKPTr0LvD89Jqk2Or5ogxz0NUMfIjhh2lIUX/LyX9B4oIg==",
+			"dev": true,
+			"funding": [
+				{
+					"type": "opencollective",
+					"url": "https://opencollective.com/browserslist"
+				},
+				{
+					"type": "tidelift",
+					"url": "https://tidelift.com/funding/github/npm/browserslist"
+				},
+				{
+					"type": "github",
+					"url": "https://github.com/sponsors/ai"
+				}
+			],
+			"license": "MIT",
+			"dependencies": {
+				"baseline-browser-mapping": "^2.10.12",
+				"caniuse-lite": "^1.0.30001782",
+				"electron-to-chromium": "^1.5.328",
+				"node-releases": "^2.0.36",
+				"update-browserslist-db": "^1.2.3"
+			},
+			"bin": {
+				"browserslist": "cli.js"
+			},
+			"engines": {
+				"node": "^6 || ^7 || ^8 || ^9 || ^10 || ^11 || ^12 || >=13.7"
+			}
+		},
 		"node_modules/callsites": {
 			"version": "3.1.0",
 			"resolved": "https://registry.npmjs.org/callsites/-/callsites-3.1.0.tgz",
@@ -3907,6 +4195,27 @@
 				"node": ">=6"
 			}
 		},
+		"node_modules/caniuse-lite": {
+			"version": "1.0.30001792",
+			"resolved": "https://registry.npmjs.org/caniuse-lite/-/caniuse-lite-1.0.30001792.tgz",
+			"integrity": "sha512-hVLMUZFgR4JJ6ACt1uEESvQN1/dBVqPAKY0hgrV70eN3391K6juAfTjKZLKvOMsx8PxA7gsY1/tLMMTcfFLLpw==",
+			"dev": true,
+			"funding": [
+				{
+					"type": "opencollective",
+					"url": "https://opencollective.com/browserslist"
+				},
+				{
+					"type": "tidelift",
+					"url": "https://tidelift.com/funding/github/npm/caniuse-lite"
+				},
+				{
+					"type": "github",
+					"url": "https://github.com/sponsors/ai"
+				}
+			],
+			"license": "CC-BY-4.0"
+		},
 		"node_modules/chai": {
 			"version": "6.2.2",
 			"resolved": "https://registry.npmjs.org/chai/-/chai-6.2.2.tgz",
@@ -4204,6 +4513,13 @@
 				"@types/trusted-types": "^2.0.7"
 			}
 		},
+		"node_modules/electron-to-chromium": {
+			"version": "1.5.353",
+			"resolved": "https://registry.npmjs.org/electron-to-chromium/-/electron-to-chromium-1.5.353.tgz",
+			"integrity": "sha512-kOrWphBi8TOZyiJZqsgqIle0lw+tzmnQK83pV9dZUd01Nm2POECSyFQMAuarzZdYqQW7FH9RaYOuaRo3h+bQ3w==",
+			"dev": true,
+			"license": "ISC"
+		},
 		"node_modules/enhanced-resolve": {
 			"version": "5.20.0",
 			"resolved": "https://registry.npmjs.org/enhanced-resolve/-/enhanced-resolve-5.20.0.tgz",
@@ -4279,6 +4595,16 @@
 				"@esbuild/win32-x64": "0.27.4"
 			}
 		},
+		"node_modules/escalade": {
+			"version": "3.2.0",
+			"resolved": "https://registry.npmjs.org/escalade/-/escalade-3.2.0.tgz",
+			"integrity": "sha512-WUj2qlxaQtO4g6Pq5c29GTcWGDyd8itL8zTlipgECz3JesAiiOKotd8JU6otB3PACgG6xkJUyVhboMS+bje/jA==",
+			"dev": true,
+			"license": "MIT",
+			"engines": {
+				"node": ">=6"
+			}
+		},
 		"node_modules/escape-string-regexp": {
 			"version": "4.0.0",
 			"resolved": "https://registry.npmjs.org/escape-string-regexp/-/escape-string-regexp-4.0.0.tgz",
@@ -4804,6 +5130,16 @@
 				"url": "https://github.com/sponsors/ljharb"
 			}
 		},
+		"node_modules/gensync": {
+			"version": "1.0.0-beta.2",
+			"resolved": "https://registry.npmjs.org/gensync/-/gensync-1.0.0-beta.2.tgz",
+			"integrity": "sha512-3hN7NaskYvMDLQY55gnW3NQ+mesEAepTqlg+VEbj7zzqEMBVNhzcGYYeqFo/TlYz6eQiFcp1HcsCZO+nGgS8zg==",
+			"dev": true,
+			"license": "MIT",
+			"engines": {
+				"node": ">=6.9.0"
+			}
+		},
 		"node_modules/get-tsconfig": {
 			"version": "4.14.0",
 			"resolved": "https://registry.npmjs.org/get-tsconfig/-/get-tsconfig-4.14.0.tgz",
@@ -5216,6 +5552,19 @@
 				}
 			}
 		},
+		"node_modules/jsesc": {
+			"version": "3.1.0",
+			"resolved": "https://registry.npmjs.org/jsesc/-/jsesc-3.1.0.tgz",
+			"integrity": "sha512-/sM3dO2FOzXjKQhJuo0Q173wf2KOo8t4I8vHy6lF9poUp7bKT0/NHE8fPX23PwfhnykfqnC2xRxOnVw5XuGIaA==",
+			"dev": true,
+			"license": "MIT",
+			"bin": {
+				"jsesc": "bin/jsesc"
+			},
+			"engines": {
+				"node": ">=6"
+			}
+		},
 		"node_modules/json-buffer": {
 			"version": "3.0.1",
 			"resolved": "https://registry.npmjs.org/json-buffer/-/json-buffer-3.0.1.tgz",
@@ -5804,6 +6153,13 @@
 			"license": "MIT",
 			"optional": true
 		},
+		"node_modules/node-releases": {
+			"version": "2.0.38",
+			"resolved": "https://registry.npmjs.org/node-releases/-/node-releases-2.0.38.tgz",
+			"integrity": "sha512-3qT/88Y3FbH/Kx4szpQQ4HzUbVrHPKTLVpVocKiLfoYvw9XSGOX2FmD2d6DrXbVYyAQTF2HeF6My8jmzx7/CRw==",
+			"dev": true,
+			"license": "MIT"
+		},
 		"node_modules/obug": {
 			"version": "2.1.1",
 			"resolved": "https://registry.npmjs.org/obug/-/obug-2.1.1.tgz",
@@ -7181,6 +7537,37 @@
 				"@unrs/resolver-binding-win32-x64-msvc": "1.11.1"
 			}
 		},
+		"node_modules/update-browserslist-db": {
+			"version": "1.2.3",
+			"resolved": "https://registry.npmjs.org/update-browserslist-db/-/update-browserslist-db-1.2.3.tgz",
+			"integrity": "sha512-Js0m9cx+qOgDxo0eMiFGEueWztz+d4+M3rGlmKPT+T4IS/jP4ylw3Nwpu6cpTTP8R1MAC1kF4VbdLt3ARf209w==",
+			"dev": true,
+			"funding": [
+				{
+					"type": "opencollective",
+					"url": "https://opencollective.com/browserslist"
+				},
+				{
+					"type": "tidelift",
+					"url": "https://tidelift.com/funding/github/npm/browserslist"
+				},
+				{
+					"type": "github",
+					"url": "https://github.com/sponsors/ai"
+				}
+			],
+			"license": "MIT",
+			"dependencies": {
+				"escalade": "^3.2.0",
+				"picocolors": "^1.1.1"
+			},
+			"bin": {
+				"update-browserslist-db": "cli.js"
+			},
+			"peerDependencies": {
+				"browserslist": ">= 4.21.0"
+			}
+		},
 		"node_modules/uri-js": {
 			"version": "4.4.1",
 			"resolved": "https://registry.npmjs.org/uri-js/-/uri-js-4.4.1.tgz",
@@ -7607,6 +7994,13 @@
 			"integrity": "sha512-JZnDKK8B0RCDw84FNdDAIpZK+JuJw+s7Lz8nksI7SIuU3UXJJslUthsi+uWBUYOwPFwW7W7PRLRfUKpxjtjFCw==",
 			"license": "MIT"
 		},
+		"node_modules/yallist": {
+			"version": "3.1.1",
+			"resolved": "https://registry.npmjs.org/yallist/-/yallist-3.1.1.tgz",
+			"integrity": "sha512-a4UGQaWPH59mOXUYnAG2ewncQS4i4F43Tv3JoAM+s2VDAmS9NsK8GpDMLrCHPksFT7h3K6TOoUNn2pb7RoXx4g==",
+			"dev": true,
+			"license": "ISC"
+		},
 		"node_modules/yaml-ast-parser": {
 			"version": "0.0.43",
 			"resolved": "https://registry.npmjs.org/yaml-ast-parser/-/yaml-ast-parser-0.0.43.tgz",
diff --git a/frontend/package.json b/frontend/package.json
index e5b5b8c9..cf279cd9 100644
--- a/frontend/package.json
+++ b/frontend/package.json
@@ -45,6 +45,7 @@
 		"@types/diff": "^7.0.2",
 		"@types/node": "^24",
 		"@vitest/browser-playwright": "^4.0.10",
+		"@vitest/coverage-istanbul": "^4.1.0",
 		"@vitest/coverage-v8": "^4.1.0",
 		"eslint": "^9.39.1",
 		"eslint-config-prettier": "^10.1.8",