fix(release): publish alias package through trusted workflow

[AgentArcLab]

Summary

• add a trusted workflow path for publishing the compatibility alias distribution agentengine-sdk-python
• keep full releases publishing both ksadk and the alias, while alias-only skips GitHub Pages redeploy
• tighten the 0.6.9 changelog summary and update the release approval record

Verification

• uv run pytest tests/test_public_release_positioning.py tests/test_prepare_ksadk_python_export.py tests/test_check_publication_state.py -q (internal)
• make public-build-alias-check (internal and public candidate)
• make public-test (public candidate)
• make public-audit (public candidate)
• KSADK_APPROVED_SOURCE_COMMIT=0ac219f0aea2214647f9a373537d39e27297c0ec make public-publish-gate (internal and public candidate)