Lemenzo Gallery v1.13 — Production Release Candidate

Final release hardening over v1.12:
- Fixed Android 16 legacy instrumentation test configuration.
  - Added android.test.base/mock/runner system stub libs to the Soong android_test target.
  - Declared android.test.runner as a uses-library inside the test application's <application> element.
- Tightened local face-based smart grouping and renamed the UI category to "Selfies & portraits" to avoid claiming identity-aware selfie classification.
- Face-based grouping now requires a single prominent centered face and rejects very wide scenes and arbitrary group photos more aggressively.
- Kept analysis strictly local/on-demand: no network, account, model download, face embeddings, identity recognition, or biometric template database.
- Nature/Animals intentionally remain unimplemented rather than using misleading heuristics. Add only with a vetted bundled offline model and explicit resource/privacy testing.
- Extended static validation to verify test-runner manifest structure, required Soong test stubs, and Java structural balance in instrumentation test sources.

Local release gates passed:
  tests/run_host_tests.sh -> PASS
  python3 tests/validate_static.py -> PASS
  XML/manifest parsing -> PASS

Final device release gates still required in the Android 16/LemenzoOS tree:
  m LemenzoGallery LemenzoGalleryTests
  atest LemenzoGalleryTests
  Pixel runtime/stress matrix in tests/TEST_PLAN.md