Remove runtime mode selection & have unified setup flow for node.js + API access

src/ipc/ipc_client.ts

@@ -13,6 +13,7 @@ import type {
   ChatStreamParams,
   CreateAppParams,
   CreateAppResult,
+  InstallNodeResult,
   ListAppsResponse,
   SandboxConfig,
   Version,
@@ -520,6 +521,17 @@ export class IpcClient {
     }
   }
 
+  // Install Node.js and npm
+  public async installNode(): Promise<InstallNodeResult> {
+    try {
+      const result = await this.ipcRenderer.invoke("install-node");
+      return result;
+    } catch (error) {
+      showError(error);
+      throw error;
+    }
+  }
+
   // --- GitHub Device Flow ---
   public startGithubDeviceFlow(appId: number | null): void {
     this.ipcRenderer.invoke("github:start-flow", { appId });