✨ feat(nutriphi): prepare for production release with tests and improved UX

- Remove broken header links to non-existent settings/profile pages
- Replace header links with settings page link
- Remove TODO comments for credit system in analysis controller
- Add comprehensive error handling with German messages in meals store
- Add loading states, retry buttons, and error displays in UI components
- Create new settings page with daily goals editor
- Add 99 tests across backend, web, and shared packages:
  - Backend: MealService, GoalsService, StatsService, FavoritesService,
    RecommendationsService, nutrition.utils (Jest)
  - Web: API client tests with mocks (Vitest)
  - Shared: utility function tests (Vitest)
- Set up test infrastructure (Jest for NestJS, Vitest for SvelteKit)

apps/nutriphi/apps/web/package.json

@@ -11,14 +11,19 @@
 		"check:watch": "svelte-kit sync && svelte-check --tsconfig ./tsconfig.json --watch",
 		"lint": "eslint .",
 		"format": "prettier --write .",
-		"type-check": "svelte-kit sync && svelte-check --tsconfig ./tsconfig.json"
+		"type-check": "svelte-kit sync && svelte-check --tsconfig ./tsconfig.json",
+		"test": "vitest run",
+		"test:watch": "vitest",
+		"test:cov": "vitest run --coverage"
 	},
 	"devDependencies": {
 		"@sveltejs/adapter-node": "^5.0.0",
 		"@sveltejs/kit": "^2.0.0",
 		"@sveltejs/vite-plugin-svelte": "^5.0.0",
 		"@tailwindcss/vite": "^4.1.7",
+		"@testing-library/svelte": "^5.2.6",
 		"@types/node": "^20.0.0",
+		"jsdom": "^25.0.1",
 		"prettier": "^3.1.1",
 		"prettier-plugin-svelte": "^3.1.2",
 		"svelte": "^5.0.0",
@@ -26,7 +31,8 @@
 		"tailwindcss": "^4.1.7",
 		"tslib": "^2.4.1",
 		"typescript": "^5.0.0",
-		"vite": "^6.0.0"
+		"vite": "^6.0.0",
+		"vitest": "^2.1.8"
 	},
 	"dependencies": {
 		"@nutriphi/shared": "workspace:*",