feat: add reusable jobqueue library

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

tests/RetryStrategy.test.ts

@@ -0,0 +1,72 @@
+import { RetryStrategy } from '../src/index.js';
+
+describe('RetryStrategy', () => {
+  it('uses exponential backoff for recoverable errors', async () => {
+    const strategy = new RetryStrategy({
+      maxAttempts: 4,
+      baseDelayMs: 100,
+      classifyError: async () => 'recoverable',
+    });
+
+    const decision = await strategy.shouldRetry(new Error('boom'), {
+      id: 'job-1',
+      status: 'active',
+      data: {},
+      currentPhase: 'run',
+      phases: [],
+      phaseResults: {},
+      progress: 0,
+      progressMessage: null,
+      error: null,
+      retryCount: 1,
+      maxAttempts: 4,
+      webhookUrl: null,
+      webhookSent: false,
+      createdAt: new Date().toISOString(),
+      startedAt: null,
+      completedAt: null,
+      updatedAt: new Date().toISOString(),
+      scheduledAt: null,
+      cancelledAt: null,
+    });
+
+    expect(decision.retry).toBe(true);
+    expect(decision.delayMs).toBe(200);
+    expect(decision.disposition).toBe('recoverable');
+  });
+
+  it('does not retry fatal errors', async () => {
+    const strategy = new RetryStrategy({
+      maxAttempts: 4,
+      classifyError: async () => 'fatal',
+    });
+
+    const decision = await strategy.shouldRetry(new Error('fatal'), {
+      id: 'job-1',
+      status: 'active',
+      data: {},
+      currentPhase: 'run',
+      phases: [],
+      phaseResults: {},
+      progress: 0,
+      progressMessage: null,
+      error: null,
+      retryCount: 0,
+      maxAttempts: 4,
+      webhookUrl: null,
+      webhookSent: false,
+      createdAt: new Date().toISOString(),
+      startedAt: null,
+      completedAt: null,
+      updatedAt: new Date().toISOString(),
+      scheduledAt: null,
+      cancelledAt: null,
+    });
+
+    expect(decision).toEqual({
+      retry: false,
+      delayMs: 0,
+      disposition: 'fatal',
+    });
+  });
+});