Update documentation and CLI behavior for GPU management

- Clarified the behavior of `Ctrl+C` and `Ctrl+D` in the README and other documentation, specifying that `Ctrl+C` only stops the tunnel while keeping the GPU active, and `Ctrl+D` stops the GPU while preserving disk data.
- Enhanced the CLI documentation to reflect these changes, ensuring users understand the implications of these commands during GPU operations.
- Improved the handling of data bindings and remounting logic in the codebase to prevent issues with empty model tabs in the UI.
- Added tests to validate the new command behaviors and ensure proper documentation alignment.

src/gpu_rent/remote/swarm_diag.py

@@ -97,6 +97,23 @@ def swarm_api_bits() -> str:
                         "current_model": val.get("current_model"),
                     }
             chunks.append("ListBackends=" + json.dumps(summary, ensure_ascii=False, indent=2))
+            try:
+                listed = _post(
+                    "/API/ListModels",
+                    {
+                        "session_id": sid,
+                        "path": "",
+                        "depth": 3,
+                        "subtype": "Stable-Diffusion",
+                    },
+                )
+                files = listed.get("files") if isinstance(listed, dict) else None
+                folders = listed.get("folders") if isinstance(listed, dict) else None
+                nfiles = len(files) if isinstance(files, list) else "?"
+                nfolders = len(folders) if isinstance(folders, list) else "?"
+                chunks.append(f"ListModels Stable-Diffusion files={nfiles} folders={nfolders}")
+            except Exception as exc:
+                chunks.append(f"ListModels fail: {exc}")
             # Full settings for first backend (StartScript path matters)
             for key, val in (backends or {}).items():
                 if isinstance(val, dict) and val.get("settings"):
@@ -125,6 +142,24 @@ def paths_bits() -> str:
         f"Backends.fds exists={BACKENDS_FDS.is_file()}",
     ]
     rows.append("findmnt /opt/swarmui/dlbackend:\n" + _run(["findmnt", "/opt/swarmui/dlbackend"]))
+    rows.append("findmnt /opt/swarmui/Models:\n" + _run(["findmnt", "/opt/swarmui/Models"]))
+    data_models = DATA / "Models"
+    opt_models = Path("/opt/swarmui/Models")
+    def _n_weights(root: Path) -> int:
+        if not root.is_dir():
+            return 0
+        n = 0
+        try:
+            for p in root.rglob("*"):
+                if p.suffix.lower() in {".safetensors", ".ckpt", ".sft"}:
+                    n += 1
+        except OSError:
+            return -1
+        return n
+
+    rows.append(
+        f"weights data={_n_weights(data_models)} swarm={_n_weights(opt_models)}"
+    )
     if SETTINGS.is_file():
         try:
             for line in SETTINGS.read_text(encoding="utf-8", errors="replace").splitlines():