Add 4 new theme colors (success, warning, error, info) with full preset support

src/app/admin/theme/page.tsx

@@ -17,6 +17,10 @@ const COLOR_FIELDS: { key: string; label: string; def: string }[] = [
   { key: "color_navbar_text", label: "Navbar text", def: "#1e293b" },
   { key: "color_text", label: "Text", def: "#0f172a" },
   { key: "color_text_muted", label: "Muted text", def: "#64748b" },
+  { key: "color_success", label: "Success", def: "#16a34a" },
+  { key: "color_warning", label: "Warning", def: "#eab308" },
+  { key: "color_error", label: "Error", def: "#ef4444" },
+  { key: "color_info", label: "Info", def: "#0ea5e9" },
 ];
 
 const BUTTON_FIELDS: { key: string; label: string; def: string }[] = [