feat(lib): implement A-4 M0~M1 BaseAgentAdapter pattern and resolve_home contract

.agents/skills/lib_py/agents/adapters/claude.py

@@ -0,0 +1,12 @@
+# claude.py — Claude Code agent adapter
+
+from lib_py.agents.base import BaseAgentAdapter
+
+class ClaudeAgentAdapter(BaseAgentAdapter):
+    @property
+    def name(self) -> str:
+        return 'claude'
+
+    @property
+    def own_key(self) -> str:
+        return 'claude_session_id_own'