feat(sdk): add durable planning runtime (#2898)

sdk/src/planning-runtime.test.ts

@@ -0,0 +1,29 @@
+import { mkdtemp } from 'node:fs/promises';
+import { tmpdir } from 'node:os';
+import { join } from 'node:path';
+import { describe, expect, it } from 'vitest';
+import { PlanningRuntime } from './planning-runtime.js';
+
+describe('PlanningRuntime', () => {
+  it('records intent events through the durable journal', async () => {
+    const dir = await mkdtemp(join(tmpdir(), 'gsd-runtime-'));
+    const runtime = new PlanningRuntime({
+      projectDir: dir,
+      projectId: 'project-1',
+      runId: 'run-1',
+      sourceId: 'sdk-1',
+      actor: { type: 'agent', id: 'agent-1', role: 'executor' },
+    });
+
+    await runtime.status({ idempotencyKey: 'status-1' });
+    await runtime.next({ idempotencyKey: 'next-1', createPlan: { title: 'Plan', items: [{ title: 'Item' }] } });
+    await runtime.checkpoint({ idempotencyKey: 'checkpoint-1', summary: 'Progress' });
+
+    const events = await runtime.journal.readAll();
+    expect(events.map((event) => event.type)).toEqual([
+      'plan.status',
+      'plan.next',
+      'plan.checkpoint',
+    ]);
+  });
+});