AUTO blocks drift detection #73

	name: AUTO blocks drift detection

	# ADR-0015 § Drift policy. Derived state (AUTO blocks + docs/INDEX.md)
	# is reconciled on demand and via this nightly cron — NOT per-PR. The
	# per-PR regen model created an O(N²) cascade on serial merges (retro
	# 544e78cc P2-9). For now this job only detects + logs drift; auto-PR
	# creation is a follow-up that needs a bot token.

	on:
	schedule:
	- cron: '17 4 * * *' # 04:17 UTC daily
	workflow_dispatch:

	jobs:
	detect-drift:
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v4
	with:
	fetch-depth: 0
	- uses: dtolnay/rust-toolchain@stable
	- run: \|
	cargo run -q -p convergio-cli -- docs regenerate
	./scripts/generate-docs-index.sh
	if git diff --quiet; then
	echo "No drift."
	exit 0
	fi
	echo "Drift detected — would open auto-PR (placeholder until cron-bot wired)."
	git diff --stat

Provide feedback