feat: add push-transcript CLI, show sessions, interactive setup, 36 tests

- cli-sync.ts: push-transcript command, show sessions with formatSessionTable(),
  upgrade cmdSetup() to interactively create .gstack-sync.json if missing
- bin/gstack-sync: add push-transcript case and help text
- test/lib-llm-summarize.test.ts: 10 tests with mocked fetch (429 retry,
  5xx backoff, malformed response, no API key, cache)
- test/lib-transcript-sync.test.ts: 22 tests for parsing, grouping,
  session file extraction, marker management, slug resolution
- test/lib-sync-show.test.ts: 4 tests for formatSessionTable

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

test/lib-llm-summarize.test.ts

@@ -0,0 +1,168 @@
+/**
+ * Tests for lib/llm-summarize.ts — mock fetch, no API calls.
+ */
+
+import { describe, test, expect, beforeEach, afterEach } from 'bun:test';
+import * as path from 'path';
+import * as os from 'os';
+import * as fs from 'fs';
+import { summarizeSession } from '../lib/llm-summarize';
+
+// Use a temp dir for cache so tests don't pollute real cache
+const tmpCacheDir = path.join(os.tmpdir(), `gstack-llm-test-${Date.now()}-${Math.random().toString(36).slice(2)}`);
+
+function makeOkResponse(text: string) {
+  return new Response(JSON.stringify({
+    content: [{ type: 'text', text }],
+    usage: { input_tokens: 100, output_tokens: 20 },
+  }), { status: 200, headers: { 'Content-Type': 'application/json' } });
+}
+
+// Each test gets unique messages to avoid cache collisions
+let testCounter = 0;
+function uniqueMessages(base: string = 'test') {
+  testCounter++;
+  return [
+    { display: `${base} prompt ${testCounter} alpha`, timestamp: 1710000000000 + testCounter },
+    { display: `${base} prompt ${testCounter} beta`, timestamp: 1710000060000 + testCounter },
+  ];
+}
+
+describe('summarizeSession', () => {
+  let originalFetch: typeof globalThis.fetch;
+  let originalApiKey: string | undefined;
+
+  beforeEach(() => {
+    originalFetch = globalThis.fetch;
+    originalApiKey = process.env.ANTHROPIC_API_KEY;
+    // Use temp cache dir and bypass cache for clean tests
+    process.env.GSTACK_STATE_DIR = tmpCacheDir;
+    process.env.EVAL_CACHE = '0'; // Skip cache reads
+  });
+
+  afterEach(() => {
+    globalThis.fetch = originalFetch;
+    if (originalApiKey !== undefined) {
+      process.env.ANTHROPIC_API_KEY = originalApiKey;
+    } else {
+      delete process.env.ANTHROPIC_API_KEY;
+    }
+    delete process.env.EVAL_CACHE;
+  });
+
+  test('returns null when ANTHROPIC_API_KEY not set', async () => {
+    delete process.env.ANTHROPIC_API_KEY;
+    const result = await summarizeSession(uniqueMessages(), ['Edit']);
+    expect(result).toBeNull();
+  });
+
+  test('returns null for empty messages', async () => {
+    process.env.ANTHROPIC_API_KEY = 'test-key';
+    const result = await summarizeSession([], ['Edit']);
+    expect(result).toBeNull();
+  });
+
+  test('returns summary on successful API call', async () => {
+    process.env.ANTHROPIC_API_KEY = 'test-key';
+    globalThis.fetch = (() => Promise.resolve(makeOkResponse('Fixed login page CSS.'))) as any;
+
+    const result = await summarizeSession(uniqueMessages('success'), ['Edit', 'Bash']);
+    expect(result).toBe('Fixed login page CSS.');
+  });
+
+  test('sends correct headers to Anthropic API', async () => {
+    process.env.ANTHROPIC_API_KEY = 'test-key-123';
+    let capturedHeaders: Record<string, string> = {};
+    globalThis.fetch = ((url: string, init: any) => {
+      for (const [k, v] of Object.entries(init.headers || {})) {
+        capturedHeaders[k] = v as string;
+      }
+      return Promise.resolve(makeOkResponse('Summary.'));
+    }) as any;
+
+    await summarizeSession(uniqueMessages('headers'), null);
+    expect(capturedHeaders['x-api-key']).toBe('test-key-123');
+    expect(capturedHeaders['anthropic-version']).toBe('2023-06-01');
+    expect(capturedHeaders['Content-Type']).toBe('application/json');
+  });
+
+  test('retries on 429 with retry-after header', async () => {
+    process.env.ANTHROPIC_API_KEY = 'test-key';
+    let callCount = 0;
+    globalThis.fetch = (() => {
+      callCount++;
+      if (callCount === 1) {
+        return Promise.resolve(new Response('', {
+          status: 429,
+          headers: { 'retry-after': '0' },
+        }));
+      }
+      return Promise.resolve(makeOkResponse('Retry succeeded.'));
+    }) as any;
+
+    const result = await summarizeSession(uniqueMessages('retry429'), null);
+    expect(result).toBe('Retry succeeded.');
+    expect(callCount).toBe(2);
+  });
+
+  test('retries on 5xx with backoff', async () => {
+    process.env.ANTHROPIC_API_KEY = 'test-key';
+    let callCount = 0;
+    globalThis.fetch = (() => {
+      callCount++;
+      if (callCount <= 2) {
+        return Promise.resolve(new Response('Server Error', { status: 500 }));
+      }
+      return Promise.resolve(makeOkResponse('Recovered.'));
+    }) as any;
+
+    const result = await summarizeSession(uniqueMessages('retry5xx'), ['Read']);
+    expect(result).toBe('Recovered.');
+    expect(callCount).toBe(3);
+  });
+
+  test('returns null on persistent 429', async () => {
+    process.env.ANTHROPIC_API_KEY = 'test-key';
+    globalThis.fetch = (() => Promise.resolve(new Response('', {
+      status: 429,
+      headers: { 'retry-after': '0' },
+    }))) as any;
+
+    const result = await summarizeSession(uniqueMessages('persistent429'), null);
+    expect(result).toBeNull();
+  });
+
+  test('returns null on 401 without retry', async () => {
+    process.env.ANTHROPIC_API_KEY = 'bad-key';
+    let callCount = 0;
+    globalThis.fetch = (() => {
+      callCount++;
+      return Promise.resolve(new Response('Unauthorized', { status: 401 }));
+    }) as any;
+
+    const result = await summarizeSession(uniqueMessages('auth401'), null);
+    expect(result).toBeNull();
+    expect(callCount).toBe(1);
+  });
+
+  test('returns null on malformed API response', async () => {
+    process.env.ANTHROPIC_API_KEY = 'test-key';
+    globalThis.fetch = (() => Promise.resolve(new Response(
+      JSON.stringify({ content: [{ type: 'image', source: {} }] }),
+      { status: 200, headers: { 'Content-Type': 'application/json' } },
+    ))) as any;
+
+    const result = await summarizeSession(uniqueMessages('malformed'), null);
+    expect(result).toBeNull();
+  });
+
+  test('truncates long summaries to 500 chars', async () => {
+    process.env.ANTHROPIC_API_KEY = 'test-key';
+    const longText = 'a'.repeat(600);
+    globalThis.fetch = (() => Promise.resolve(makeOkResponse(longText))) as any;
+
+    const result = await summarizeSession(uniqueMessages('longtext'), null);
+    expect(result).not.toBeNull();
+    expect(result!.length).toBeLessThanOrEqual(500);
+  });
+});