feat: pending-finish proposals and QQ image input

Proposal semantics: worker results no longer distinguish success/fail;
only an explicit finish settles a pending proposal. Pending owner input
follows up by resuming the original worker session. Dirty pending blocks
start_next globally; clean pending only blocks its owner.

QQ adapter now downloads image attachments and passes them as ACP image
content blocks; video/file attachments degrade to link text.

test/qq-adapter.test.ts

@@ -31,6 +31,125 @@ test("group messages without member_openid fall back to user_openid", async () =
   assert.equal(received[1].userId, "mem4");
 });
 
+test("image attachments are downloaded to base64 while video and file attachments degrade to text links", async () => {
+  const received: any[] = [];
+  const gateway = { receive: async (message: unknown) => { received.push(message); } };
+  const adapter = new QqAdapter(config, gateway as never);
+  const pngBytes = Buffer.from("fake-png-bytes");
+  const urls: string[] = [];
+  const original = globalThis.fetch;
+  globalThis.fetch = (async (input: string | URL | Request) => {
+    urls.push(String(input));
+    return new Response(pngBytes, { status: 200 });
+  }) as typeof fetch;
+  try {
+    await adapter.handleWebhook({
+      body: {
+        op: 0, t: "C2C_MESSAGE_CREATE",
+        d: {
+          id: "m10", author: { user_openid: "u10" }, content: "看看这些",
+          attachments: [
+            { content_type: "image/png", filename: "a.png", size: pngBytes.length, url: "//cdn.example.com/a.png" },
+            { content_type: "video/mp4", filename: "v.mp4", size: 1024, url: "https://cdn.example.com/v.mp4" },
+            { content_type: "application/pdf", filename: "f.pdf", size: 1024, url: "https://cdn.example.com/f.pdf" }
+          ]
+        }
+      },
+      headers: {}, query: {}, req: {} as never
+    });
+    await new Promise((resolve) => setImmediate(resolve));
+    assert.equal(received.length, 1);
+    const message = received[0];
+    assert.deepEqual(urls, ["https://cdn.example.com/a.png"]);
+    assert.equal(message.attachments.length, 1);
+    assert.equal(message.attachments[0].mimeType, "image/png");
+    assert.equal(message.attachments[0].filename, "a.png");
+    assert.equal(message.attachments[0].data, pngBytes.toString("base64"));
+    assert.match(message.text, /^看看这些/);
+    assert.match(message.text, /\[视频\] https:\/\/cdn\.example\.com\/v\.mp4/);
+    assert.match(message.text, /\[文件\] https:\/\/cdn\.example\.com\/f\.pdf/);
+  } finally { globalThis.fetch = original; }
+});
+
+test("oversized images are skipped and images beyond the per-message cap are not downloaded", async () => {
+  const received: any[] = [];
+  const gateway = { receive: async (message: unknown) => { received.push(message); } };
+  const adapter = new QqAdapter(config, gateway as never);
+  const urls: string[] = [];
+  const original = globalThis.fetch;
+  globalThis.fetch = (async (input: string | URL | Request) => {
+    urls.push(String(input));
+    return new Response(Buffer.from("x"), { status: 200 });
+  }) as typeof fetch;
+  try {
+    await adapter.handleWebhook({
+      body: {
+        op: 0, t: "C2C_MESSAGE_CREATE",
+        d: {
+          id: "m11", author: { user_openid: "u11" }, content: "hi",
+          attachments: [
+            { content_type: "image/png", size: 6 * 1024 * 1024, url: "https://cdn.example.com/big.png" },
+            { content_type: "image/png", size: 10, url: "https://cdn.example.com/1.png" },
+            { content_type: "image/png", size: 10, url: "https://cdn.example.com/2.png" },
+            { content_type: "image/png", size: 10, url: "https://cdn.example.com/3.png" },
+            { content_type: "image/png", size: 10, url: "https://cdn.example.com/4.png" }
+          ]
+        }
+      },
+      headers: {}, query: {}, req: {} as never
+    });
+    await new Promise((resolve) => setImmediate(resolve));
+    assert.equal(received.length, 1);
+    assert.deepEqual(urls, [
+      "https://cdn.example.com/1.png",
+      "https://cdn.example.com/2.png",
+      "https://cdn.example.com/3.png"
+    ]);
+    assert.equal(received[0].attachments.length, 3);
+  } finally { globalThis.fetch = original; }
+});
+
+test("a pure image message uses placeholder text and failed downloads degrade", async () => {
+  const received: any[] = [];
+  const gateway = { receive: async (message: unknown) => { received.push(message); } };
+  const adapter = new QqAdapter(config, gateway as never);
+  const original = globalThis.fetch;
+  let fail = false;
+  globalThis.fetch = (async () => {
+    if (fail) throw new Error("network down");
+    return new Response(Buffer.from("img"), { status: 200 });
+  }) as typeof fetch;
+  try {
+    await adapter.handleWebhook({
+      body: { op: 0, t: "C2C_MESSAGE_CREATE", d: { id: "m12", author: { user_openid: "u12" }, content: "", attachments: [{ content_type: "image/jpeg", url: "https://cdn.example.com/a.jpg" }] } },
+      headers: {}, query: {}, req: {} as never
+    });
+    await new Promise((resolve) => setImmediate(resolve));
+    assert.equal(received.length, 1);
+    assert.equal(received[0].text, "（发来一张图片）");
+    assert.equal(received[0].attachments.length, 1);
+
+    // Every download failing with no text keeps the message ignored.
+    fail = true;
+    await adapter.handleWebhook({
+      body: { op: 0, t: "C2C_MESSAGE_CREATE", d: { id: "m13", author: { user_openid: "u12" }, content: "", attachments: [{ content_type: "image/jpeg", url: "https://cdn.example.com/b.jpg" }] } },
+      headers: {}, query: {}, req: {} as never
+    });
+    await new Promise((resolve) => setImmediate(resolve));
+    assert.equal(received.length, 1);
+
+    // Failed downloads with text still deliver the text without attachments.
+    await adapter.handleWebhook({
+      body: { op: 0, t: "C2C_MESSAGE_CREATE", d: { id: "m14", author: { user_openid: "u12" }, content: "看图", attachments: [{ content_type: "image/jpeg", url: "https://cdn.example.com/c.jpg" }] } },
+      headers: {}, query: {}, req: {} as never
+    });
+    await new Promise((resolve) => setImmediate(resolve));
+    assert.equal(received.length, 2);
+    assert.equal(received[1].text, "看图");
+    assert.equal(received[1].attachments, undefined);
+  } finally { globalThis.fetch = original; }
+});
+
 test("sendMessage uses C2C endpoint and forwards reply sequences as msg_seq", async () => {
   const original = globalThis.fetch; const urls: string[] = []; const bodies: Array<Record<string, unknown>> = [];
   globalThis.fetch = (async (input: string | URL | Request, init?: RequestInit) => {