fix(security): rate limit web_fetch tool to mitigate DDoS via prompt injection (#19567)

Co-authored-by: gemini-code-assist[bot] <176961590+gemini-code-assist[bot]@users.noreply.github.com>

packages/core/src/scheduler/tool-executor.ts

@@ -192,6 +192,8 @@ export class ToolExecutor {
       tool: call.tool,
       invocation: call.invocation,
       durationMs: startTime ? Date.now() - startTime : undefined,
+      startTime,
+      endTime: Date.now(),
       outcome: call.outcome,
     };
   }
@@ -263,6 +265,8 @@ export class ToolExecutor {
       response: successResponse,
       invocation: call.invocation,
       durationMs: startTime ? Date.now() - startTime : undefined,
+      startTime,
+      endTime: Date.now(),
       outcome: call.outcome,
     };
   }
@@ -287,6 +291,8 @@ export class ToolExecutor {
       response,
       tool: call.tool,
       durationMs: startTime ? Date.now() - startTime : undefined,
+      startTime,
+      endTime: Date.now(),
       outcome: call.outcome,
     };
   }