[zhaozhaozz]

Changes to dashboard source files such as static/ need a collection run to copy them into site/ before Pages can publish them. Add a small workflow that dispatches collect.yml on main after source changes, using the repository GITHUB_TOKEN and a push-<full SHA> request ID.

The dispatcher ignores pushes that only change site/** and .sync/**, so collection commits cannot dispatch another collection. It does not run on pull requests or cancel active collection runs. Existing scheduled, manual and Bot dispatches remain available, and Pages still publishes on site/ changes.

collect.yml remains limited to schedule and workflow_dispatch: its Worker OIDC trust rejects a direct push event. No collector, token broker or concurrency changes are included.

Validation:

• Parsed the workflow YAML and checked triggers, path exclusions, permissions and the unchanged collector configuration.
• Checked shell syntax and executed the dispatch step with an offline gh stub; verified the repository, collect.yml, main ref and valid request ID, with no source_repository input.
• PYTHONDONTWRITEBYTECODE=1 python3 -m unittest discover -s tests -p 'test_collection_context.py' -v: 4 tests passed.
• git diff --check: passed.

No collection was manually dispatched during validation.