Fix admin AI nav bug, add rescan feature

- Fix Blade parse error in admin AI settings (Blade was interpreting
  JSON braces in DEFAULT_PROMPT as template tags, breaking the navbar)
  — pass defaultPrompt from controller instead
- Add rescan: POST /nail-polishes/{id}/rescan creates a new import for
  an existing nail polish and updates its fields after AI analysis
- Add KI-Rescan button on collection cards (only if image exists)

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

app/Http/Controllers/NailPolishImportController.php

@@ -3,6 +3,7 @@
 namespace App\Http\Controllers;
 
 use App\Jobs\ProcessNailPolishImage;
+use App\Models\NailPolish;
 use App\Models\NailPolishImport;
 use Illuminate\Http\Request;
 use Illuminate\Support\Facades\Storage;
@@ -63,9 +64,25 @@ class NailPolishImportController extends Controller
 
     public function show(NailPolishImport $nailPolishImport)
     {
-        // Nur eigene Imports ansehen
         abort_if($nailPolishImport->user_id !== auth()->id(), 403);
 
         return view('nail-polish-imports.show', ['import' => $nailPolishImport->load('nailPolish.manufacturer')]);
     }
+
+    public function rescan(NailPolish $nailPolish)
+    {
+        abort_unless($nailPolish->image_path, 404);
+
+        $import = NailPolishImport::create([
+            'user_id'        => auth()->id(),
+            'image_path'     => $nailPolish->image_path,
+            'status'         => 'pending',
+            'nail_polish_id' => $nailPolish->id,
+        ]);
+
+        ProcessNailPolishImage::dispatch($import->id);
+
+        return redirect()->route('nail-polish-imports.show', $import)
+            ->with('success', 'KI-Analyse gestartet. Die Daten werden aktualisiert.');
+    }
 }