feat(P03 W7): secret rotation scheduled workflow (SPEC §5.9)

workflows-src/rotate-aws-key.yml — daily cron (0 0 * * *) + workflow_dispatch,
wraps scripts/rotate_spike_key.sh (uses NOVA_AWS_* static-key auth to IAM-
rotate the nova-spike-runner key; uploads the new key to the consumer's
Actions secret store; idempotent — deactivates the old key only after the
new propagates, verified by a post-PUT GET). Synced to .github + .gitea.
v0.2 scope: the mechanism exists (SPEC §5.9 — exists-not-ran); the v0.2
deploy uses the currently-active key. Documented in ARCHITECTURE.md §12.9.

The synced workflow file is forge-agnostic (REQ-230): forge base URL /
owner / consumer repo come from repository secrets (NOVA_FORGE_*,
NOVA_CONSUMER_REPO), not literals. rotate_spike_key.sh reads NOVA_FORGE_*
with NOVA_GITEA_* backward-compat fallback. sync_workflows.py PAIRS
extended to include rotate-aws-key.yml (was hardcoded to 3 pairs).

---ci---
project: acdl
phase: 3
milestone: v1.26
status: execute
wave: W7
---

scripts/sync_workflows.py

@@ -2,7 +2,7 @@
 """Sync byte-identical workflows from workflows-src/ to .gitea/ + .github/ (P8, REQ-172).
 
 Three workflow pairs are byte-identical Gitea + GitHub mirrors:
-  ci.yml, deploy.yml, modules-lifecycle.yml.
+  ci.yml, deploy.yml, modules-lifecycle.yml, rotate-aws-key.yml.
 
 This generator reads the single source from ``workflows-src/<name>`` and
 writes byte-identical copies to both ``.gitea/workflows/<name>`` and
@@ -26,7 +26,7 @@ SRC_DIR = ROOT / "workflows-src"
 GITEA_DIR = ROOT / ".gitea" / "workflows"
 GITHUB_DIR = ROOT / ".github" / "workflows"
 
-PAIRS = ["ci.yml", "deploy.yml", "modules-lifecycle.yml"]
+PAIRS = ["ci.yml", "deploy.yml", "modules-lifecycle.yml", "rotate-aws-key.yml"]
 
 
 def _read_source(name: str) -> str: