feat(a4,c3b): complete A-4 Phase 2 agent knowledge migration & Option B isolation removal

- Option B / C-3b: Deprecate isolation.root and remove its 4 legacy consumers in lib.sh, workspace_uuid.py, verify_session.py, and stop_session.sh.
- M2~M7 Migration: Implement artifact_path, verify_artifact, purge_artifacts, spawn_spec, resume_spec, auth_ok, discover, ready_tokens, exit_key, and delegate_agent_key across BaseAgentAdapter and all 4 adapters (Claude, Agy, Hermes, Cline).
- Migrate shell duplications in lib.sh, create_session.sh, resume_session.sh, stop_session.sh, and reconcile.sh to python -m lib_py.agents facts.
- Hardening & Corrections: Fix Cline resume_spec flag to '-i --id', apply shlex.quote across all facts variables with MAM_ prefix, add safe fallback in wait_for_tui_ready.
- Add comprehensive contract tests in tests/test_a4_adapter_contract.py and sync IMPROVEMENTS.md / LOG.md.
- Verified: 100% PASS across unit, component, contract, and integration tests.

.agents/skills/lib_py/agents/__main__.py

@@ -1,6 +1,6 @@
 # __main__.py — CLI bridge for lib_py.agents facts and resolution (N4)
 
-import sys, json
+import sys, json, shlex
 from lib_py.agents.registry import get_adapter, own_key, agent_of_row
 
 def main():
@@ -16,11 +16,15 @@ def main():
             print(f"ERROR: Unknown agent {agent_name!r}", file=sys.stderr)
             sys.exit(1)
         # Emit shell-eval friendly facts
-        print(f"AGENT_NAME={adapter.name}")
-        print(f"OWN_KEY={adapter.own_key}")
-        print(f"INPUT_PROMPT={adapter.input_prompt or ''}")
-        print(f"INPUT_PLACEHOLDER={adapter.input_placeholder or ''}")
-        print(f"INPUT_RULE_PATTERN={adapter.input_rule_pattern or ''}")
+        q = shlex.quote
+        print(f"MAM_AGENT_NAME={q(adapter.name)}")
+        print(f"MAM_OWN_KEY={q(adapter.own_key)}")
+        print(f"MAM_INPUT_PROMPT={q(adapter.input_prompt or '')}")
+        print(f"MAM_INPUT_PLACEHOLDER={q(adapter.input_placeholder or '')}")
+        print(f"MAM_INPUT_RULE_PATTERN={q(adapter.input_rule_pattern or '')}")
+        print(f"MAM_READY_TOKENS={q(adapter.ready_tokens)}")
+        print(f"MAM_EXIT_KEY={q(adapter.exit_key)}")
+        print(f"MAM_DELEGATE_AGENT_KEY={q(adapter.delegate_agent_key)}")
 
     elif cmd == 'resolve':
         name = sys.argv[2] if len(sys.argv) > 2 else ''