config: add vitest coverage include pattern + lcov reporter (#10575)

## What

- Add `include: ['src/**/*.{ts,vue}']` to vitest coverage config so ALL
source files appear in reports (previously only imported files showed
up)
- Add `lcov` reporter for CI integration and VS Code coverage gutter
- Add `exclude` patterns for test files, locales, litegraph, assets,
declarations, stories
- Add `test:coverage` npm script

## Why

Coverage reports currently only show files that are imported during test
runs. Adding the `include` pattern reveals the true gap — files with
zero coverage that were previously invisible. The lcov reporter enables
IDE integration and future CI coverage comments (Codecov/Coveralls).

## Testing

`npx tsc --noEmit` passes. No behavioral changes — this only affects
coverage reporting configuration.

┆Issue is synchronized with this [Notion
page](https://www.notion.so/PR-10575-config-add-vitest-coverage-include-pattern-lcov-reporter-32f6d73d365081c8b59ad2316dd2b198)
by [Unito](https://www.unito.io)

.github/workflows/ci-tests-unit.yaml

@@ -1,4 +1,4 @@
-# Description: Unit and component testing with Vitest
+# Description: Unit and component testing with Vitest + coverage reporting
 name: 'CI: Tests Unit'
 
 on:
@@ -23,5 +23,12 @@ jobs:
       - name: Setup frontend
         uses: ./.github/actions/setup-frontend
 
-      - name: Run Vitest tests
-        run: pnpm test:unit
+      - name: Run Vitest tests with coverage
+        run: pnpm test:coverage
+
+      - name: Upload coverage to Codecov
+        if: always()
+        uses: codecov/codecov-action@1af58845a975a7985b0beb0cbe6fbbb71a41dbad # v5.5.3
+        with:
+          files: coverage/lcov.info
+          fail_ci_if_error: false

package.json

@@ -45,6 +45,7 @@
     "stylelint": "stylelint --cache '{apps,packages,src}/**/*.{css,vue}'",
     "test:browser": "pnpm exec nx e2e",
     "test:browser:local": "cross-env PLAYWRIGHT_LOCAL=1 PLAYWRIGHT_TEST_URL=http://localhost:5173 pnpm test:browser",
+    "test:coverage": "vitest run --coverage",
     "test:unit": "nx run test",
     "typecheck": "vue-tsc --noEmit",
     "typecheck:browser": "vue-tsc --project browser_tests/tsconfig.json",

vite.config.mts

@@ -653,7 +653,18 @@ export default defineConfig({
       'scripts/**/*.{test,spec}.{js,mjs,cjs,ts,mts,cts,jsx,tsx}'
     ],
     coverage: {
-      reporter: ['text', 'json', 'html']
+      provider: 'v8',
+      reporter: ['text', 'json', 'html', 'lcov'],
+      include: ['src/**/*.{ts,vue}'],
+      exclude: [
+        'src/**/*.test.ts',
+        'src/**/*.spec.ts',
+        'src/**/*.stories.ts',
+        'src/**/*.d.ts',
+        'src/locales/**',
+        'src/lib/litegraph/**',
+        'src/assets/**'
+      ]
     },
     exclude: [
       '**/node_modules/**',