refactor: deepen query failure classification module

sdk/src/query-failure-classification.test.ts

@@ -0,0 +1,28 @@
+import { describe, expect, it } from 'vitest';
+import {
+  errorMessage,
+  isTimeoutLikeError,
+  isTimeoutMessage,
+  parseTimeoutMs,
+  timeoutMessage,
+} from './query-failure-classification.js';
+
+describe('query failure classification', () => {
+  it('extracts timeout metadata from message', () => {
+    const msg = timeoutMessage('state', ['load'], 30000);
+    expect(isTimeoutMessage(msg)).toBe(true);
+    expect(parseTimeoutMs(msg)).toBe(30000);
+  });
+
+  it('classifies timeout-like errors', () => {
+    expect(isTimeoutLikeError(new Error('gsd-tools timed out after 1000ms: x'))).toBe(true);
+    const abort = new Error('aborted');
+    abort.name = 'AbortError';
+    expect(isTimeoutLikeError(abort)).toBe(true);
+  });
+
+  it('normalizes unknown error values', () => {
+    expect(errorMessage('boom')).toBe('boom');
+    expect(errorMessage(new Error('x'))).toBe('x');
+  });
+});