Allow manual runs of CI and CodeQL via workflow_dispatch

[AndreasIgel]

Fixes #203

Summary

Adds a workflow_dispatch: trigger to the CI and CodeQL workflows so maintainers can start them manually from the Actions tab (a "Run workflow" button), without pushing an artificial commit.

# .github/workflows/maven.yml  and  .github/workflows/codeql.yml
 on:
   push: ...
   pull_request: ...
+  workflow_dispatch:

Scope / rationale

• Purely additive — existing push / pull_request (and CodeQL schedule) triggers are unchanged.
• Useful for re-running the security scan / full build+coverage on demand after config changes (secrets, branch protection, scanner settings) or for incident response. Mirrors the release workflow, which already has workflow_dispatch.
• dependency-review.yml is intentionally excluded: dependency-review-action needs a base/head to diff and errors on a plain workflow_dispatch run unless explicit base-ref/head-ref inputs are wired (out of scope).

Validation

• actionlint clean on both workflows.

Related

The fork-PR quality workflows added in #186 (fork-coverage.yml, fork-sonar.yml) carry their own workflow_dispatch trigger (with a run_id input) in that PR, since those files live on #186's branch. This PR covers the manual trigger for maven.yml and codeql.yml.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ All tests successful. No failed tests found.

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