test: run the suite and benchmark with Bun's native test runner

Replace Vitest with bun test across the whole suite. A preload compiles
components through Angular's JIT transform with inlined templates, sets
up jsdom, TestBed and zoneless change detection, and a small shim covers
the Vitest APIs bun:test lacks. Files run isolated, real-worker specs
spawn the running Bun, and line coverage from lcov is converted to the
existing HTML and Cobertura reports. The CI benchmark replaces its heap
cap with a container memory limit. Vitest, Jest, Nx and their Vite
configuration are removed.

Refs #291

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

.gitea/workflows/ci.yml

@@ -52,18 +52,19 @@ jobs:
         name: test
         runs-on: ubuntu-latest
         container: node:24.21.0
-        env:
-            NODE_OPTIONS: --max-old-space-size=2048
         steps:
             - uses: https://gitea.com/actions/checkout@v4
               with:
                   persist-credentials: false
-            - run: npm install --global bun@1.4.2
+            - run: npm install --global bun@1.4.3
             - run: bun install --frozen-lockfile
             - run: bun scripts/generate-langs.js
             - name: Functional coverage
-              run: bunx vitest run --coverage --maxWorkers=1 --exclude='src/app/benchmark/**'
+              run: bun test --config=bunfig.coverage.toml --isolate --path-ignore-patterns='**/benchmark/**'
             - name: Coverage report
+              if: ${{ always() }}
+              run: bun scripts/coverage-reports.mjs
+            - name: Upload coverage
               if: ${{ always() }}
               uses: https://gitea.com/actions/upload-artifact@v3
               with:
@@ -75,18 +76,18 @@ jobs:
     benchmark:
         name: benchmark
         runs-on: ubuntu-latest
-        container: node:24.21.0
-        env:
-            NODE_OPTIONS: --max-old-space-size=2048
+        container:
+            image: node:24.21.0
+            options: --memory=3g
         steps:
             - uses: https://gitea.com/actions/checkout@v4
               with:
                   persist-credentials: false
-            - run: npm install --global bun@1.4.2
+            - run: npm install --global bun@1.4.3
             - run: bun install --frozen-lockfile
             - run: bun scripts/generate-langs.js
             - name: Benchmark protocol with relative gate
-              run: timeout 600s bunx vitest run src/app/benchmark/ --maxWorkers=1
+              run: timeout 600s bun test src/app/benchmark --timeout=600000
 
     build:
         name: build