feat(mvp): working secrets-engine CLI for the whynot-design npm publish lane

Implements SECRETS-WP-0002 end to end as a uv-managed Python package:

- catalog: non-secret lane registry + strict validator (build/test/prod)
- stage roles + OpenBao ACL policies; guards refuse wildcards, sys/, identity/,
  admin names, and cross-stage paths before any backend call
- plan/apply: dry-run-first, idempotent policy + approle apply, decision-gated
- decisions: State Hub lookup with local-fixture fallback; non-secret evidence
  to JSONL + hub progress, scrubbed of any value
- provision/verify: mode-0600 file import + generated test values; positive/
  negative checks that never print the value
- exec delivery: `exec --catalog ... -- npm publish` injects the token via a
  temp .npmrc for the child only, cleaned up on exit/failure/interrupt
- ops-warden routing contract + hardening backlog docs
- 34 tests incl. live OpenBao integration; scripts/demo-e2e.sh runs the full
  chain against a throwaway bao dev server

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

.repo-classification.yaml

@@ -1,18 +1,26 @@
 repo_classification:
   standard: Repo Classification Standard
   version: '1.0'
-  classified_at: '2026-06-22'
-  classified_by: agent
+  classified_at: '2026-06-28'
+  classified_by: codex
   category: tooling
   domain: infotech
-  secondary_domains: []
+  secondary_domains:
+  - financials
   capability_tags:
   - platform
   - configuration
-  - documentation
+  - orchestration
+  - governance
+  - policy
   business_stake:
   - technology
+  - operations
+  - automation
   - execution
   business_mechanics:
   - operation
-  notes: Git template for bootstrapping coulomb projects.
+  - control
+  - coordination
+  - adaptation
+  notes: OpenBao-backed secrets workflow and automation layer for approved build, test, and production secret lifecycle work.