refactor: deepen query failure classification module

sdk/src/query-failure-classification.ts

@@ -0,0 +1,24 @@
+export function errorMessage(error: unknown): string {
+  return error instanceof Error ? error.message : String(error);
+}
+
+export function parseTimeoutMs(message: string): number | undefined {
+  const m = message.match(/timed out after\s+(\d+)ms/i);
+  if (!m) return undefined;
+  const n = Number.parseInt(m[1], 10);
+  return Number.isFinite(n) ? n : undefined;
+}
+
+export function isTimeoutMessage(message: string): boolean {
+  return /timed out after/i.test(message);
+}
+
+export function isTimeoutLikeError(error: unknown): boolean {
+  if (!(error instanceof Error)) return false;
+  if (error.name === 'TimeoutError' || error.name === 'AbortError') return true;
+  return isTimeoutMessage(error.message);
+}
+
+export function timeoutMessage(command: string, args: string[], timeoutMs: number): string {
+  return `gsd-tools timed out after ${timeoutMs}ms: ${command} ${args.join(' ')}`;
+}