docs(agent): correct resolve_context_cwd comment (None → caller getcwd fallback, not skip)

agent/runtime_cwd.py

@@ -25,7 +25,9 @@ def resolve_agent_cwd() -> Path:
 
 
 def resolve_context_cwd() -> Path | None:
-    # None is load-bearing: it signals "skip context-file discovery" so the
-    # gateway install dir's AGENTS.md isn't slurped (see system_prompt.py).
+    # None means "no configured cwd": build_context_files_prompt then falls back
+    # to the launch dir (os.getcwd()) — correct for the local CLI. The gateway
+    # avoids slurping its install dir by setting TERMINAL_CWD (see system_prompt.py).
+    # No getcwd arm here: that fallback is owned by the caller, not this resolver.
     raw = os.environ.get("TERMINAL_CWD", "").strip()
     return Path(raw).expanduser() if raw else None