✨ Add project detail page with prev/next navigation (Story 2.3)

- Enhance ProjectController show() with prev/next navigation data
- Create useFetchProject composable with ProjectNavigation type
- Implement [slug].vue with full project details:
  - Hero image, title with featured badge, formatted date
  - Description, external links (site/GitHub)
  - Skills grid with level progression (before → after)
  - Prev/next navigation with project titles
  - 404 state with spider narrator
- Add dynamic SEO meta tags with og:image from project
- Responsive design: stacked mobile, grid desktop

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

api/app/Http/Controllers/Api/ProjectController.php

@@ -5,6 +5,7 @@ namespace App\Http\Controllers\Api;
 use App\Http\Controllers\Controller;
 use App\Http\Resources\ProjectResource;
 use App\Models\Project;
+use App\Models\Translation;
 
 class ProjectController extends Controller
 {
@@ -18,9 +19,39 @@ class ProjectController extends Controller
 
     public function show(string $slug)
     {
-        $project = Project::with('skills')->where('slug', $slug)->firstOrFail();
+        $project = Project::with('skills')->where('slug', $slug)->first();
+
+        if (!$project) {
+            return response()->json([
+                'error' => [
+                    'code' => 'PROJECT_NOT_FOUND',
+                    'message' => 'Project not found',
+                ],
+            ], 404);
+        }
+
+        $lang = app()->getLocale();
+
+        // Get all projects in order for navigation
+        $allProjects = Project::ordered()->get(['id', 'slug', 'title_key']);
+        $currentIndex = $allProjects->search(fn ($p) => $p->slug === $slug);
+
+        $prev = $currentIndex > 0 ? $allProjects[$currentIndex - 1] : null;
+        $next = $currentIndex < $allProjects->count() - 1 ? $allProjects[$currentIndex + 1] : null;
 
         return (new ProjectResource($project))
-            ->additional(['meta' => ['lang' => app()->getLocale()]]);
+            ->additional([
+                'meta' => ['lang' => $lang],
+                'navigation' => [
+                    'prev' => $prev ? [
+                        'slug' => $prev->slug,
+                        'title' => Translation::getTranslation($prev->title_key, $lang),
+                    ] : null,
+                    'next' => $next ? [
+                        'slug' => $next->slug,
+                        'title' => Translation::getTranslation($next->title_key, $lang),
+                    ] : null,
+                ],
+            ]);
     }
 }