Sync upstream Gemini-CLI v0.8.2 (#838)

packages/core/src/utils/errors.ts

@@ -59,6 +59,16 @@ export class FatalTurnLimitedError extends FatalError {
     super(message, 53);
   }
 }
+export class FatalToolExecutionError extends FatalError {
+  constructor(message: string) {
+    super(message, 54);
+  }
+}
+export class FatalCancellationError extends FatalError {
+  constructor(message: string) {
+    super(message, 130); // Standard exit code for SIGINT
+  }
+}
 
 export class ForbiddenError extends Error {}
 export class UnauthorizedError extends Error {}