test: migrate unit tests from Karma to Vitest (#66)

Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Author: Helias

.github/workflows/tests.yml

@@ -26,4 +26,4 @@ jobs:
         run: npm ci
 
       - name: Run unit tests
-        run: npx ng test --watch=false --browsers=ChromeHeadless
+        run: npx ng test --watch=false

angular.json

@@ -15,11 +15,11 @@
       "prefix": "app",
       "architect": {
         "build": {
-          "builder": "@angular-devkit/build-angular:application",
+          "builder": "@angular/build:application",
           "options": {
             "outputPath": "dist/server-status",
             "index": "src/index.html",
-            "polyfills": ["src/polyfills.ts"],
+            "polyfills": ["zone.js"],
             "tsConfig": "tsconfig.app.json",
             "assets": ["src/favicon.ico", "src/assets"],
             "styles": [
@@ -66,7 +66,7 @@
           "defaultConfiguration": ""
         },
         "serve": {
-          "builder": "@angular-devkit/build-angular:dev-server",
+          "builder": "@angular/build:dev-server",
           "options": {
             "buildTarget": "server-status:build"
           },
@@ -77,21 +77,17 @@
           }
         },
         "extract-i18n": {
-          "builder": "@angular-devkit/build-angular:extract-i18n",
+          "builder": "@angular/build:extract-i18n",
           "options": {
             "buildTarget": "server-status:build"
           }
         },
         "test": {
-          "builder": "@angular-devkit/build-angular:karma",
+          "builder": "@angular/build:unit-test",
           "options": {
-            "main": "src/test.ts",
-            "polyfills": "src/polyfills.ts",
+            "buildTarget": "server-status:build",
             "tsConfig": "tsconfig.spec.json",
-            "karmaConfig": "karma.conf.js",
-            "assets": ["src/favicon.ico", "src/assets"],
-            "styles": ["src/styles.scss"],
-            "scripts": []
+            "runner": "vitest"
           }
         },
         "e2e": {