refactor(search): remove NLP/smart-search feature entirely (#772)

## Summary

- Removes the NLP/smart-search feature completely — the feature was too unreliable and slow; users get better results with the regular search filters
- Deletes the entire backend `search/` package (NlSearchController, NlQueryParserService, NlpClient, NlSearchRateLimiter — 14 classes + 6 test classes)
- Deletes the `nlp-service/` Python microservice (FastAPI, rapidfuzz, DB-backed person matching)
- Removes all frontend NL search components: SmartModeToggle, SmartSearchStatus, InterpretationChipRow, DisambiguationPicker, chip-types, theme-chip-removal
- Strips smart-mode logic from SearchFilterBar and documents/+page.svelte
- Removes `SMART_SEARCH_UNAVAILABLE` / `SMART_SEARCH_RATE_LIMITED` error codes from backend, frontend types, and all three i18n files (de/en/es)
- Removes `nlp-service` container and `APP_NLP_BASE_URL` from both docker-compose files
- Removes Ollama/NLP Prometheus scrape job and Grafana dashboard
- Deletes ADRs 028 (×2), 034, 035

## Test plan

- [ ] Backend compiles: `cd backend && ./mvnw compile -q` → BUILD SUCCESS
- [ ] Frontend server tests pass: `cd frontend && npm run test -- --project=server`
- [ ] No NLP/smart-search references remain in source: `grep -r "SmartSearch\|NlSearch\|nlp-service\|SMART_SEARCH" backend/src frontend/src`
- [ ] `docker compose config` validates both compose files
- [ ] Search page loads, filter bar works, no smart-mode toggle visible

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-authored-by: Marcel <marcel@familienarchiv>
Reviewed-on: #772

frontend/src/lib/generated/api.ts

@@ -228,22 +228,6 @@ export interface paths {
         patch?: never;
         trace?: never;
     };
-    "/api/search/nl": {
-        parameters: {
-            query?: never;
-            header?: never;
-            path?: never;
-            cookie?: never;
-        };
-        get?: never;
-        put?: never;
-        post: operations["search"];
-        delete?: never;
-        options?: never;
-        head?: never;
-        patch?: never;
-        trace?: never;
-    };
     "/api/persons": {
         parameters: {
             query?: never;
@@ -1835,9 +1819,6 @@ export interface components {
             /** Format: uuid */
             targetId: string;
         };
-        NlSearchRequest: {
-            query: string;
-        };
         Pageable: {
             /** Format: int32 */
             page?: number;
@@ -1897,34 +1878,6 @@ export interface components {
             /** Format: int32 */
             length: number;
         };
-        NlQueryInterpretation: {
-            resolvedPersons: components["schemas"]["PersonHint"][];
-            ambiguousPersons: components["schemas"]["PersonHint"][];
-            /** Format: date */
-            dateFrom?: string;
-            /** Format: date */
-            dateTo?: string;
-            keywords: string[];
-            resolvedTags: components["schemas"]["TagHint"][];
-            rawQuery: string;
-            keywordsApplied: boolean;
-            tagsApplied: boolean;
-        };
-        NlSearchResponse: {
-            result: components["schemas"]["DocumentSearchResult"];
-            interpretation: components["schemas"]["NlQueryInterpretation"];
-        };
-        PersonHint: {
-            /** Format: uuid */
-            id: string;
-            displayName: string;
-        };
-        TagHint: {
-            /** Format: uuid */
-            id: string;
-            name: string;
-            color?: string;
-        };
         SearchMatchData: {
             transcriptionSnippet?: string;
             titleOffsets: components["schemas"]["MatchOffset"][];
@@ -3244,32 +3197,6 @@ export interface operations {
             };
         };
     };
-    search: {
-        parameters: {
-            query: {
-                pageable: components["schemas"]["Pageable"];
-            };
-            header?: never;
-            path?: never;
-            cookie?: never;
-        };
-        requestBody: {
-            content: {
-                "application/json": components["schemas"]["NlSearchRequest"];
-            };
-        };
-        responses: {
-            /** @description OK */
-            200: {
-                headers: {
-                    [name: string]: unknown;
-                };
-                content: {
-                    "*/*": components["schemas"]["NlSearchResponse"];
-                };
-            };
-        };
-    };
     getPersons: {
         parameters: {
             query?: {