fix(tui): preserve remote cwd for ssh sessions

tui_gateway/server.py

@@ -813,6 +813,30 @@ def _completion_cwd(params: dict | None = None) -> str:
     return os.getcwd()
 
 
+def _terminal_task_cwd(session: dict | None) -> str:
+    """Return the cwd that terminal_tool should use for this TUI session.
+
+    ``_completion_cwd`` validates paths on the host so file completion does not
+    point at nonsense.  Non-local terminal backends are different: their cwd is
+    inside the target environment, so an SSH path like /home/user/workspace may
+    not exist on the local macOS host but is still the correct execution cwd.
+    """
+    backend = (os.environ.get("TERMINAL_ENV") or "").strip().lower()
+    if backend and backend != "local":
+        raw = os.environ.get("TERMINAL_CWD", "").strip()
+        if not raw:
+            try:
+                terminal_cfg = _load_cfg().get("terminal", {})
+                if isinstance(terminal_cfg, dict):
+                    raw = str(terminal_cfg.get("cwd") or "").strip()
+            except Exception:
+                raw = ""
+        if raw and raw not in {".", "auto", "cwd"}:
+            return raw
+
+    return _session_cwd(session)
+
+
 def _git_branch_for_cwd(cwd: str) -> str:
     try:
         result = subprocess.run(
@@ -851,7 +875,7 @@ def _register_session_cwd(session: dict | None) -> None:
         from tools.terminal_tool import register_task_env_overrides
 
         register_task_env_overrides(
-            session["session_key"], {"cwd": _session_cwd(session)}
+            session["session_key"], {"cwd": _terminal_task_cwd(session)}
         )
     except Exception:
         pass