feat: add OpenCode CLI support with status endpoint

- Implemented OpenCode CLI installation and authentication status check.
- Added new route for OpenCode status in setup routes.
- Updated HttpApiClient to include method for fetching OpenCode status.
- Enhanced system paths to include OpenCode's default installation directories.

This commit introduces functionality to check the installation and authentication status of the OpenCode CLI, improving integration with the overall system.

apps/ui/src/lib/http-api-client.ts

@@ -1284,6 +1284,32 @@ export class HttpApiClient implements ElectronAPI {
       error?: string;
     }> => this.post('/api/setup/verify-codex-auth', { authMethod, apiKey }),
 
+    // OpenCode CLI methods
+    getOpencodeStatus: (): Promise<{
+      success: boolean;
+      status?: string;
+      installed?: boolean;
+      method?: string;
+      version?: string;
+      path?: string;
+      recommendation?: string;
+      installCommands?: {
+        macos?: string;
+        linux?: string;
+        npm?: string;
+      };
+      auth?: {
+        authenticated: boolean;
+        method: string;
+        hasAuthFile?: boolean;
+        hasOAuthToken?: boolean;
+        hasApiKey?: boolean;
+        hasStoredApiKey?: boolean;
+        hasEnvApiKey?: boolean;
+      };
+      error?: string;
+    }> => this.get('/api/setup/opencode-status'),
+
     onInstallProgress: (callback: (progress: unknown) => void) => {
       return this.subscribeToEvent('agent:stream', callback);
     },