fix: address self-review findings for Vercel Sandbox salvage

- Add vercel_sandbox to hardline blocklist container bypass test
- Add vercel_sandbox to skills_tool remote backend parametrize test
- Deduplicate runtime set: doctor.py and setup.py now import
  _SUPPORTED_VERCEL_RUNTIMES from terminal_tool.py
- Add docstring to _run_bash explaining timeout/stdin_data discards
- Always stop sandbox during cleanup (unconditional, matching Modal/Daytona)
- Update security.md: container bypass text, production tip, comparison table
- Update environment-variables.md: TERMINAL_ENV list, Vercel auth vars,
  TERMINAL_VERCEL_RUNTIME
- Update inline comments in cli.py and config.py to include vercel_sandbox

hermes_cli/config.py

@@ -500,7 +500,7 @@ DEFAULT_CONFIG = {
         "modal_image": "nikolaik/python-nodejs:python3.11-nodejs20",
         "daytona_image": "nikolaik/python-nodejs:python3.11-nodejs20",
         "vercel_runtime": "node24",
-        # Container resource limits (docker, singularity, modal, daytona — ignored for local/ssh)
+        # Container resource limits (docker, singularity, modal, daytona, vercel_sandbox — ignored for local/ssh)
         "container_cpu": 1,
         "container_memory": 5120,       # MB (default 5GB)
         "container_disk": 51200,        # MB (default 50GB)

hermes_cli/doctor.py

@@ -868,11 +868,13 @@ def run_doctor(args):
     # Vercel Sandbox (if using vercel_sandbox backend)
     if terminal_env == "vercel_sandbox":
         runtime = os.getenv("TERMINAL_VERCEL_RUNTIME", "node24").strip() or "node24"
-        if runtime in {"node24", "node22", "python3.13"}:
+        from tools.terminal_tool import _SUPPORTED_VERCEL_RUNTIMES
+        if runtime in _SUPPORTED_VERCEL_RUNTIMES:
             check_ok("Vercel runtime", f"({runtime})")
         else:
-            check_fail("Vercel runtime unsupported", f"({runtime}; use node24, node22, or python3.13)")
-            issues.append("Set TERMINAL_VERCEL_RUNTIME to node24, node22, or python3.13")
+            supported = ", ".join(_SUPPORTED_VERCEL_RUNTIMES)
+            check_fail("Vercel runtime unsupported", f"({runtime}; use {supported})")
+            issues.append(f"Set TERMINAL_VERCEL_RUNTIME to one of: {supported}")
 
         disk = os.getenv("TERMINAL_CONTAINER_DISK", "51200").strip()
         if disk in ("", "0", "51200"):

hermes_cli/setup.py

@@ -666,11 +666,14 @@ def _prompt_vercel_sandbox_settings(config: dict):
     print_info("  Filesystem persistence uses Vercel snapshots.")
     print_info("  Snapshots restore files only; live processes do not continue after sandbox recreation.")
 
+    from tools.terminal_tool import _SUPPORTED_VERCEL_RUNTIMES
+
     current_runtime = terminal.get("vercel_runtime") or "node24"
-    runtime = prompt("  Runtime (node24, node22, python3.13)", current_runtime).strip() or current_runtime
-    if runtime not in {"node24", "node22", "python3.13"}:
+    supported_label = ", ".join(_SUPPORTED_VERCEL_RUNTIMES)
+    runtime = prompt(f"  Runtime ({supported_label})", current_runtime).strip() or current_runtime
+    if runtime not in _SUPPORTED_VERCEL_RUNTIMES:
         print_warning(f"Unsupported Vercel runtime '{runtime}', keeping {current_runtime}.")
-        runtime = current_runtime if current_runtime in {"node24", "node22", "python3.13"} else "node24"
+        runtime = current_runtime if current_runtime in _SUPPORTED_VERCEL_RUNTIMES else "node24"
     terminal["vercel_runtime"] = runtime
     save_env_value("TERMINAL_VERCEL_RUNTIME", runtime)
 

hermes_cli/web_server.py

@@ -258,7 +258,7 @@ _SCHEMA_OVERRIDES: Dict[str, Dict[str, Any]] = {
     "terminal.vercel_runtime": {
         "type": "select",
         "description": "Vercel Sandbox runtime",
-        "options": ["node24", "node22", "python3.13"],
+        "options": ["node24", "node22", "python3.13"],  # sync with _SUPPORTED_VERCEL_RUNTIMES in terminal_tool.py
     },
     "terminal.modal_mode": {
         "type": "select",