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/adapters/claude.py

@@ -1,6 +1,7 @@
-# claude.py — Claude Code agent adapter
-
-from lib_py.agents.base import BaseAgentAdapter
+import os, json, glob, subprocess
+from typing import Optional, Any
+from lib_py.agents.base import BaseAgentAdapter, DiscoveryContext
+from lib_py.verify_session import workspace_key
 
 class ClaudeAgentAdapter(BaseAgentAdapter):
     @property
@@ -11,6 +12,22 @@ class ClaudeAgentAdapter(BaseAgentAdapter):
     def own_key(self) -> str:
         return 'claude_session_id_own'
 
+    @property
+    def ready_tokens(self) -> str:
+        return 'Anthropic|Assistant|Chat|Welcome'
+
+    @property
+    def exit_key(self) -> str:
+        return '/exit'
+
+    @property
+    def delegate_agent_key(self) -> str:
+        return 'claude-code'
+
+    @property
+    def identity_cache_fields(self) -> tuple:
+        return ('session_id', 'session_jsonl', 'session_size_bytes', 'session_lines')
+
     @property
     def input_prompt(self) -> str:
         return '❯'
@@ -22,3 +39,83 @@ class ClaudeAgentAdapter(BaseAgentAdapter):
     @property
     def input_rule_pattern(self) -> str:
         return '─{10,}'
+
+    def artifact_path(self, uuid: str, ctx: DiscoveryContext) -> str:
+        return f"{ctx.claude_dir}/{ctx.ws_key}/{uuid}.jsonl"
+
+    def verify_artifact(self, uuid: str, ctx: DiscoveryContext) -> bool:
+        path = self.artifact_path(uuid, ctx)
+        if not os.path.exists(path):
+            return False
+        if ctx.epoch and os.path.getmtime(path) < ctx.epoch:
+            return False
+        try:
+            valid_session = False
+            found_cwd = None
+            with open(path) as f:
+                for _ in range(50):
+                    line = f.readline()
+                    if not line:
+                        break
+                    line = line.strip()
+                    if not line:
+                        continue
+                    try:
+                        payload = json.loads(line)
+                        if payload.get("sessionId") == uuid:
+                            valid_session = True
+                        if payload.get("cwd"):
+                            found_cwd = payload.get("cwd")
+                            break
+                    except Exception:
+                        pass
+            if not valid_session:
+                return False
+            if found_cwd and workspace_key(found_cwd) != workspace_key(ctx.cwd):
+                return False
+        except Exception:
+            return False
+        return True
+
+    def purge_artifacts(self, uuid: str, ctx: DiscoveryContext) -> list:
+        jsonl = self.artifact_path(uuid, ctx)
+        if os.path.exists(jsonl):
+            os.remove(jsonl)
+            return [jsonl]
+        return []
+
+    def spawn_spec(self, binary: str, session_uuid: str = "", use_wrapper: bool = False) -> str:
+        if use_wrapper or not session_uuid:
+            return f"{binary} --dangerously-skip-permissions"
+        return f"{binary} --dangerously-skip-permissions --session-id {session_uuid}"
+
+    def resume_spec(self, binary: str, session_uuid: str, materialized: bool = False) -> str:
+        if materialized and session_uuid:
+            return f"{binary} --dangerously-skip-permissions -r {session_uuid}"
+        elif session_uuid:
+            return f"{binary} --dangerously-skip-permissions --session-id {session_uuid}"
+        return f"{binary} --dangerously-skip-permissions"
+
+    def auth_ok(self, run_cmd: Optional[Any] = None) -> bool:
+        if run_cmd is not None:
+            try:
+                rc, stdout, stderr = run_cmd(['claude', 'auth', 'status'])
+                return rc == 0 and ('"loggedIn":true' in (stdout or '').replace(' ', ''))
+            except Exception:
+                return False
+        try:
+            res = subprocess.run(['claude', 'auth', 'status'], capture_output=True, text=True)
+            return res.returncode == 0 and ('"loggedIn":true' in (res.stdout or '').replace(' ', ''))
+        except Exception:
+            return False
+
+    def discover(self, ctx: DiscoveryContext) -> list:
+        key = workspace_key(ctx.workspace)
+        proj = f"{ctx.claude_dir}/{key}"
+        candidates = []
+        if os.path.isdir(proj):
+            for j in sorted(glob.glob(f"{proj}/*.jsonl"), key=os.path.getmtime, reverse=True):
+                cand = os.path.basename(j)[:-6]
+                if cand and self.verify_artifact(cand, ctx):
+                    candidates.append(cand)
+        return candidates