Add instance nav prefs, env config UI, and PM2 restart.

P1-P4: configurable nav/section visibility in system settings, full .env editor with restart badges, password change, runtime hot overrides, and single-instance pm2 restart. Works in hub embed iframe.
Co-authored-by: Cursor <cursoragent@cursor.com>

lib/instance/instance_embed_lib.py

@@ -19,6 +19,7 @@ EMBED_TABS: tuple[str, ...] = (
     "records",
     "stats",
     "risk_policy",
+    "env_config",
     "settings",
 )
 
@@ -34,6 +35,7 @@ PATH_TO_EMBED_TAB: dict[str, str] = {
     "/records": "records",
     "/stats": "stats",
     "/risk_policy": "risk_policy",
+    "/env_config": "env_config",
     "/settings": "settings",
 }
 
@@ -166,6 +168,9 @@ def register_embed_routes(
         tab = (tab or "").strip()
         if tab not in EMBED_TABS:
             return jsonify({"ok": False, "msg": "unknown tab"}), 404
+        allowed_fn = app.config.get("INSTANCE_TAB_ALLOWED_FN")
+        if callable(allowed_fn) and not allowed_fn(tab):
+            return jsonify({"ok": False, "msg": "tab disabled"}), 403
         html = render_main_page_fn(tab, embed_mode="fragment")
         if isinstance(html, Response):
             html = html.get_data(as_text=True)