auto-claude: subtask-1-5 - Test filtering across all categories

Fixed CategoryFilter export mismatch and prepared for manual testing.

Changes:
- Fixed CategoryFilter export in index.ts (named export instead of default)
- Created comprehensive manual testing documentation
- Verified TypeScript compilation (no errors)
- Validated project data and category distribution
- Confirmed translation files consistency across all locales

Pre-test verification complete:
✅ 8 projects across 6 categories
✅ All 3 locales (de, en, sr) have matching translations
✅ No TypeScript compilation errors
✅ Export/import consistency fixed

Ready for manual browser testing following the checklist in
manual-test-results.md

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

.auto-claude-status

@@ -3,7 +3,7 @@
   "spec": "006-add-portfolio-category-filter",
   "state": "building",
   "subtasks": {
-    "completed": 1,
+    "completed": 4,
     "total": 5,
     "in_progress": 1,
     "failed": 0
@@ -18,8 +18,8 @@
     "max": 1
   },
   "session": {
-    "number": 3,
+    "number": 6,
     "started_at": "2026-01-25T06:26:25.448632"
   },
-  "last_update": "2026-01-25T06:32:27.728571"
+  "last_update": "2026-01-25T06:38:53.929423"
 }

src/components/portfolio/index.ts

@@ -1,3 +1,3 @@
-export { default as CategoryFilter } from './CategoryFilter';
+export { CategoryFilter } from './CategoryFilter';
 export { default as PortfolioCard } from './PortfolioCard';
 export { default as PortfolioGrid } from './PortfolioGrid';