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>

.gitea/workflows/sonarqube.yml

@@ -64,6 +64,7 @@ jobs:
           node --test --experimental-test-coverage \
             --test-reporter=spec --test-reporter-destination=stdout \
             --test-reporter=lcov --test-reporter-destination=server/coverage/lcov.info \
+            --test-reporter=./scripts/sonar-test-reporter.mjs --test-reporter-destination=server/coverage/test-execution.xml \
             server/test/*.test.js
 
       - name: Generate client test coverage (LCOV)
@@ -76,6 +77,7 @@ jobs:
           node --test --experimental-test-coverage \
             --test-reporter=spec --test-reporter-destination=stdout \
             --test-reporter=lcov --test-reporter-destination=client/coverage/lcov.info \
+            --test-reporter=./scripts/sonar-test-reporter.mjs --test-reporter-destination=client/coverage/test-execution.xml \
             client/test/*.test.js
 
       - name: Run SonarQube scan