Phase 0: Add frontend module config and update settings store

- Created modules.config.ts with module definitions
- Added ModuleEnableSettings API functions
- Updated settingsStore with module enable settings support
- Added isModuleEnabled helper method

frontend/src/services/api.ts

@@ -1474,6 +1474,20 @@ export async function deleteAccountSetting(key: string): Promise<void> {
 }
 
 // Module Settings
+export interface ModuleEnableSettings {
+  id: number;
+  planner_enabled: boolean;
+  writer_enabled: boolean;
+  thinker_enabled: boolean;
+  automation_enabled: boolean;
+  site_builder_enabled: boolean;
+  linker_enabled: boolean;
+  optimizer_enabled: boolean;
+  publisher_enabled: boolean;
+  created_at: string;
+  updated_at: string;
+}
+
 export interface ModuleSetting {
   id: number;
   module_name: string;
@@ -1498,6 +1512,19 @@ export async function createModuleSetting(data: { module_name: string; key: stri
   });
 }
 
+export async function fetchModuleEnableSettings(): Promise<ModuleEnableSettings> {
+  const response = await fetchAPI('/v1/system/settings/modules/enable/');
+  return response;
+}
+
+export async function updateModuleEnableSettings(data: Partial<ModuleEnableSettings>): Promise<ModuleEnableSettings> {
+  const response = await fetchAPI('/v1/system/settings/modules/enable/', {
+    method: 'PUT',
+    body: JSON.stringify(data),
+  });
+  return response;
+}
+
 export async function updateModuleSetting(moduleName: string, key: string, data: Partial<{ config: Record<string, any>; is_active: boolean }>): Promise<ModuleSetting> {
   return fetchAPI(`/v1/system/settings/modules/${key}/?module_name=${moduleName}`, {
     method: 'PUT',