feat: add Codex CLI detection and model management APIs

- Implemented IPC handlers for checking Codex CLI installation status, retrieving available models, and checking provider statuses.
- Enhanced the SettingsView to include OpenAI API key management and connection testing.
- Updated the feature executor to support multiple model providers (Claude and Codex), allowing for improved flexibility in feature execution.
- Introduced utility functions to determine model types and support for thinking controls.

This update enhances the application's capabilities by integrating Codex CLI support and improving model management, providing users with a more robust experience.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

app/src/lib/electron.ts

@@ -42,7 +42,7 @@ export interface StatResult {
 }
 
 // Auto Mode types - Import from electron.d.ts to avoid duplication
-import type { AutoModeEvent } from "@/types/electron";
+import type { AutoModeEvent, ModelDefinition, ProviderStatus } from "@/types/electron";
 
 export interface AutoModeAPI {
   start: (projectPath: string) => Promise<{ success: boolean; error?: string }>;
@@ -94,6 +94,39 @@ export interface ElectronAPI {
     };
     error?: string;
   }>;
+  checkCodexCli?: () => Promise<{
+    success: boolean;
+    status?: string;
+    method?: string;
+    version?: string;
+    path?: string;
+    hasApiKey?: boolean;
+    recommendation?: string;
+    installCommands?: {
+      macos?: string;
+      windows?: string;
+      linux?: string;
+      npm?: string;
+    };
+    error?: string;
+  }>;
+  model?: {
+    getAvailable: () => Promise<{
+      success: boolean;
+      models?: ModelDefinition[];
+      error?: string;
+    }>;
+    checkProviders: () => Promise<{
+      success: boolean;
+      providers?: Record<string, ProviderStatus>;
+      error?: string;
+    }>;
+  };
+  testOpenAIConnection?: (apiKey?: string) => Promise<{
+    success: boolean;
+    message?: string;
+    error?: string;
+  }>;
 }
 
 declare global {
@@ -359,6 +392,28 @@ export const getElectronAPI = (): ElectronAPI => {
       return { success: true, path: tempFilePath };
     },
 
+    checkClaudeCli: async () => ({
+      success: false,
+      status: "not_installed",
+      recommendation: "Claude CLI checks are unavailable in the web preview.",
+    }),
+
+    checkCodexCli: async () => ({
+      success: false,
+      status: "not_installed",
+      recommendation: "Codex CLI checks are unavailable in the web preview.",
+    }),
+
+    model: {
+      getAvailable: async () => ({ success: true, models: [] }),
+      checkProviders: async () => ({ success: true, providers: {} }),
+    },
+
+    testOpenAIConnection: async () => ({
+      success: false,
+      error: "OpenAI connection test is only available in the Electron app.",
+    }),
+
     // Mock Auto Mode API
     autoMode: createMockAutoModeAPI(),
   };