restructure: flatten workspace nesting, move devcontainer to root

- backend/workspaces/backend/ → backend/
- backend/workspaces/frontend/ → frontend/
- backend/.devcontainer/ + .vscode/ → repo root (where VS Code expects them)
- loose scripts/SQL files → scripts/
- replace nested git repo with single repo at project root
- update docker-compose.yml build context and devcontainer.json path
- add root .gitignore

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

frontend/src/routes/login/+page.svelte

@@ -0,0 +1,33 @@
+<script lang="ts">
+    // TypeScript Typen für die Form-Antwort
+    export let form: { error?: string, success?: boolean };
+</script>
+
+<div class="min-h-screen flex items-center justify-center">
+    <div class="bg-white p-8 rounded shadow-md w-96">
+        <h1 class="text-2xl font-bold mb-6 text-center">Familienarchiv</h1>
+
+        <form method="POST" action="?/login" class="space-y-4">
+            <div>
+                <label for="username" class="block text-sm font-medium text-gray-700">Benutzername</label>
+                <input type="text" name="username" id="username" required 
+                       class="mt-1 block w-full rounded border-gray-300 shadow-sm p-2 border" />
+            </div>
+
+            <div>
+                <label for="password" class="block text-sm font-medium text-gray-700">Passwort</label>
+                <input type="password" name="password" id="password" required 
+                       class="mt-1 block w-full rounded border-gray-300 shadow-sm p-2 border" />
+            </div>
+
+            {#if form?.error}
+                <div class="text-red-600 text-sm text-center">{form.error}</div>
+            {/if}
+
+            <button type="submit" 
+                    class="bg-brand-navy text-white h-[42px] rounded text-sm font-bold uppercase hover:bg-brand-mint hover:text-brand-navy w-full">
+                Anmelden
+            </button>
+        </form>
+    </div>
+</div>