ci: centralize path-gating behind single orchestrator + all-checks-pass
gate
Replace the scattered per-workflow detect-changes pattern with a single
ci.yml orchestrator that runs the classifier once, then conditionally
calls sub-workflows via workflow_call based on lane outputs. A final
all-checks-pass job (if: always()) aggregates all results so branch
protection only needs to require one check.
Changes:
- New .github/workflows/ci.yml orchestrator (detect + conditional calls
+ all-checks-pass gate)
- Extend classify_changes.py with scan/deps/mcp_catalog lanes, absorbing
supply-chain-audit's internal changes job
- Update detect-changes/action.yml to expose the new lane outputs
- Convert all 10 PR-gated sub-workflows to workflow_call-only triggers,
removing their push/pull_request triggers and per-step detect-changes
guards (gating now happens at the orchestrator level)
- lint.yml + supply-chain-audit.yml receive event_name as a
workflow_call
input to replace github.event_name (which is "workflow_call" inside
called workflows)
- supply-chain-audit.yml: remove internal changes job + *-gate jobs
(orchestrator handles gating, booleans arrive as inputs)
- contributor-check.yml: remove internal filter step
- Update test_classify_changes.py for 6-lane output + new supply-chain
test cases
Heavy PR checks run on every PR because the workflows deliberately avoid
`on.paths` filters — a path-gated workflow leaves its required check pending
forever when no matching file changes, blocking merge. So a docs-only PR
still spins up the TypeScript matrix, the full Python suite, and ruff/ty.
Keep every workflow triggering on every PR (checks always report) but gate
the expensive *steps* on what the PR touches. Skipping a step (not the job)
leaves the job green, so required checks never hang — the same idiom already
proven in contributor-check.yml.
A classifier (scripts/ci/classify_changes.py) maps the PR diff to three
lanes — python, frontend, site — surfaced as step outputs by a composite
action (.github/actions/detect-changes). Fail-open: an empty diff or any
.github/ change runs everything; python is a denylist (skipped only when
every file is provably prose or a frontend-only package); skills/**/SKILL.md
counts as python-relevant since the skill-doc tests read that tree. Non-PR
events always run the full pipeline.