Replace inSubAgent flag with subAgentInvocationId for tool calling loop checks

Author: bhavyaus

src/extension/prompt/node/searchSubagentToolCallingLoop.ts

@@ -54,7 +54,7 @@ export class SearchSubagentToolCallingLoop extends ToolCallingLoop<ISearchSubage
 			context.tools = {
 				...context.tools,
 				toolReferences: [],
-				inSubAgent: true
+				subAgentInvocationId: randomUUID()
 			};
 		}
 		context.query = this.options.promptText;

src/extension/tools/node/codebaseTool.tsx

@@ -152,7 +152,7 @@ export class CodebaseTool implements vscode.LanguageModelTool<ICodebaseToolParam
 		const isAnonymous = !this.authenticationService.anyGitHubSession;
 
 		// Don't trigger nested tool calling loop if we're already in a subagent
-		if (this._input?.tools?.inSubAgent) {
+		if (this._input?.tools?.subAgentInvocationId) {
 			return false;
 		}