fix(b22b): retarget composites + delete stale anthropic-cloud/v1

Phase 8 cutover (M22) renamed the anthropic harness from anthropic-cloud
→ anthropic-cloud-paul-oauth in agent-runtimes, but the equivalent
rename in this framework's composites and the deletion of the stale
SOPS-era anthropic-cloud/v1 dir were never done. Every cloud-Anthropic
composite (haiku/sonnet/opus code, planning, security-review, spec-
writing, test-writing, best-practices) layered the dead context and
silently never resolved a credential.

- Update 14 composites to layer anthropic-cloud-paul-oauth/v1
- Delete the orphaned harnesses/contexts/anthropic-cloud/v1/ directory
  (used pre-Phase-9 SOPS file delivery; now obsolete)

Closes BUG-22b. Pairs with the live PATCH /v1/accounts/{id} rename
shipped under BUG-22a.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

harnesses/composites/best-practices-opus-repo/v1/harness.yaml

@@ -5,6 +5,6 @@ description: "Best practices review agent with Opus + repo clone via SSH"
 
 layers:
   - context: best-practices/v1
-  - context: anthropic-cloud/v1
+  - context: anthropic-cloud-paul-oauth/v1
   - context: gitea-ssh/v1
   - context: agent-repo/v1