ci(sonarqube): report test execution so the Unit Tests measure populates

The lcov reports only feed SonarQube's Coverage metric — the "Unit Tests" tile
stayed "-" because we never provided a test-execution report (a separate input
via sonar.testExecutionReportPaths, in SonarQube's own Generic Test Execution
XML format, which the lcov/junit reporters don't produce).

Add a dependency-free custom node:test reporter (scripts/sonar-test-reporter.mjs)
that emits that XML — repo-root-relative <file path> entries matching sonar.tests,
integer-ms durations — and wire it into both the server and client coverage runs
in sonarqube.yml, plus sonar.testExecutionReportPaths in sonar-project.properties.

Verified locally: server 380 + client 43 test cases, well-formed XML, all three
reporters (spec/lcov/sonar) coexist in one `node --test` invocation.

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

scripts/sonar-test-reporter.mjs

@@ -0,0 +1,64 @@
+// Custom node:test reporter that emits SonarQube's Generic Test Execution XML.
+//
+// Node's built-in reporters give us coverage (`lcov`) and pass/fail output
+// (`spec`/`tap`/`junit`), but SonarQube's "Unit Tests" measure is fed by a
+// SEPARATE report in *its own* format via `sonar.testExecutionReportPaths` — the
+// lcov report only populates Coverage, which is why the dashboard shows coverage
+// while the Unit Tests tile stays "-". This reporter produces that missing report.
+//
+// Format: https://docs.sonarsource.com/sonarqube/latest/analyzing-source-code/test-coverage/generic-test-data/
+//   <testExecutions version="1">
+//     <file path="server/test/foo.test.js">
+//       <testCase name="..." duration="12"/>      <!-- duration = integer ms -->
+//     </file>
+//   </testExecutions>
+//
+// Paths are emitted repo-root-relative (POSIX separators) so they match the
+// `sonar.tests` roots; the workflow runs `node --test` from the repo root, so the
+// absolute `file` on each event strips cleanly against process.cwd().
+import path from 'node:path'
+
+function xmlEscape(s) {
+  return String(s).replace(/[<>&"']/g, (c) => ({
+    '<': '&lt;',
+    '>': '&gt;',
+    '&': '&amp;',
+    '"': '&quot;',
+    "'": '&apos;',
+  })[c])
+}
+
+export default async function* sonarTestReporter(source) {
+  const byFile = new Map()
+  const cwd = process.cwd()
+
+  for await (const event of source) {
+    if (event.type !== 'test:pass' && event.type !== 'test:fail') continue
+    const d = event.data
+    // Skip the container events (a `describe` suite) and anything without a file
+    // — only real test cases go in the report, so the count matches the runner's.
+    if (!d.file || (d.details && d.details.type === 'suite')) continue
+
+    const rel = path.relative(cwd, d.file).split(path.sep).join('/')
+    if (!byFile.has(rel)) byFile.set(rel, [])
+    byFile.get(rel).push({
+      name: d.name,
+      duration: Math.max(0, Math.round(d.details?.duration_ms ?? 0)),
+      failed: event.type === 'test:fail',
+      skipped: Boolean(d.skip || d.todo),
+    })
+  }
+
+  yield '<?xml version="1.0" encoding="UTF-8"?>\n<testExecutions version="1">\n'
+  for (const [file, cases] of byFile) {
+    yield `  <file path="${xmlEscape(file)}">\n`
+    for (const c of cases) {
+      const attrs = `name="${xmlEscape(c.name)}" duration="${c.duration}"`
+      if (c.failed) yield `    <testCase ${attrs}><failure message="test failed"/></testCase>\n`
+      else if (c.skipped) yield `    <testCase ${attrs}><skipped/></testCase>\n`
+      else yield `    <testCase ${attrs}/>\n`
+    }
+    yield '  </file>\n'
+  }
+  yield '</testExecutions>\n'
+}