[extensions] Add extension management install command (#6703)

packages/core/src/config/config.ts

@@ -205,6 +205,7 @@ export interface ConfigParameters {
   useRipgrep?: boolean;
   shouldUseNodePtyShell?: boolean;
   skipNextSpeakerCheck?: boolean;
+  extensionManagement?: boolean;
   enablePromptCompletion?: boolean;
 }
 
@@ -275,6 +276,7 @@ export class Config {
   private readonly useRipgrep: boolean;
   private readonly shouldUseNodePtyShell: boolean;
   private readonly skipNextSpeakerCheck: boolean;
+  private readonly extensionManagement: boolean;
   private readonly enablePromptCompletion: boolean = false;
   private initialized: boolean = false;
   readonly storage: Storage;
@@ -349,6 +351,7 @@ export class Config {
     this.useRipgrep = params.useRipgrep ?? false;
     this.shouldUseNodePtyShell = params.shouldUseNodePtyShell ?? false;
     this.skipNextSpeakerCheck = params.skipNextSpeakerCheck ?? false;
+    this.extensionManagement = params.extensionManagement ?? false;
     this.storage = new Storage(this.targetDir);
     this.enablePromptCompletion = params.enablePromptCompletion ?? false;
     this.fileExclusions = new FileExclusions(this);
@@ -678,6 +681,10 @@ export class Config {
     return this.listExtensions;
   }
 
+  getExtensionManagement(): boolean {
+    return this.extensionManagement;
+  }
+
   getExtensions(): GeminiCLIExtension[] {
     return this._extensions;
   }