fix(agents): harden shell adapter bridge and address double-check review feedback

- create_session.sh: add explicit case fallback for delegate_agent (R1)
- lib_py.agents: add spawn-spec, resume-spec, exit-key argv CLI subcommands (R2)
- resume_session.sh, stop_session.sh: replace python string interpolation with safe argv subcommands (R2)
- stop_session.sh: dynamically iterate adapter.identity_cache_fields (R3)
- verify_session.py, workspace_uuid.py: remove dead imports (R9/N4)
- tests/test_a4_adapter_contract.py: add CLI bridge subcommand, clean-env PYTHONPATH safety, and fallback contract tests (R12/N1)
- SKILL.md, docs, logs: synchronize IMPROVEMENTS.md, LOG.md, and resolve_session_id wording (R8/R10/R11)
- promote verified peer review reports for cline (e7b9812b) and claude (31730364)

.agents/skills/multi-agent-mux-resume/SKILL.md

@@ -67,7 +67,7 @@ SESSION_NAME=<workspace>-creator-<agent>  # same convention as multi-agent-mux-c
 # Resolve the isolated herdr server name & load common utils
 source .agents/skills/lib.sh
 
-# 1. Resolve the session id (T5: pass session name for target-row isolation check)
+# 1. Resolve the session id (pass session name to prefer target-row recorded id)
 UUID=$(bash .agents/skills/multi-agent-mux-resume/scripts/resolve_session_id.sh \
   --workspace "$WORKSPACE" --agent "$AGENT" --session "$SESSION_NAME")