fix(hub): download Feishu resources via bot-owned lark-cli

Agent tool downloads and trigger attachment staging both used the SDK
messageResource path, which fails closed for multi-MB teacher files and
did not share the bot-identity transport contract. Route every download
through Hub-owned createFeishuBotCli (secret via stdin, disposable HOME,
HUB_FEISHU_CLI_BIN), keep workspace containment on write, and inject the
adapter in trigger tests.

hub/test/unit/feishu-download.test.ts

@@ -5,6 +5,8 @@ import { Readable } from "node:stream";
 import { describe, expect, it, vi } from "vitest";
 import { claudeSdkToolConfigForRole, cphHubMcpToolsForRole } from "../../src/agent/roleTools.js";
 import type { FeishuRuntime } from "../../src/feishu/client.js";
+import type { FeishuBotCli } from "../../src/feishu/botCli.js";
+import { writeNewWorkspaceFileNoFollow } from "../../src/security/workspaceFiles.js";
 import { downloadFeishuMessageResource } from "../../src/feishu/download.js";
 
 const itOnLinux = process.platform === "linux" ? it : it.skip;
@@ -27,14 +29,12 @@ describe("Feishu message resource download", () => {
     await mkdir(workspaceDir);
     try {
       const messageGet = vi.fn(async () => ({ data: { items: [{ chat_id: "chat-1" }] } }));
-      const messageResourceGet = vi.fn(async () => ({
-        getReadableStream: () => Readable.from([Buffer.from("image bytes")]),
-      }));
+      const messageResourceGet = vi.fn();
       const rt = mockRuntime(messageGet, messageResourceGet);
-
+      const botCli = fakeBotCli();
       const result = await downloadFeishuMessageResource(
         { messageId: "message-1", fileKey: "img-key-1", resourceType: "image" },
-        { boundChatId: "chat-1", workspaceRoot, workspaceDir },
+        { boundChatId: "chat-1", workspaceRoot, workspaceDir, botCli },
         rt,
       );
 
@@ -44,10 +44,7 @@ describe("Feishu message resource download", () => {
       );
       expect(result.path).toMatch(/\.png$/);
       await expect(readFile(result.path, "utf8")).resolves.toBe("image bytes");
-      expect(messageResourceGet).toHaveBeenCalledWith({
-        params: { type: "image" },
-        path: { message_id: "message-1", file_key: "img-key-1" },
-      });
+      expect(messageResourceGet).not.toHaveBeenCalled();
     } finally {
       await rm(workspaceRoot, { recursive: true, force: true });
     }
@@ -60,10 +57,14 @@ describe("Feishu message resource download", () => {
 
     await expect(downloadFeishuMessageResource(
       { messageId: "message-other", fileKey: "img-key-other", resourceType: "image" },
-      { boundChatId: "chat-1", workspaceRoot: "/tmp", workspaceDir: "/tmp/project-1" },
+      {
+        boundChatId: "chat-1",
+        workspaceRoot: "/tmp",
+        workspaceDir: "/tmp/project-1",
+        botCli: fakeBotCli(),
+      },
       rt,
     )).rejects.toThrow("current project's bound chat");
-    expect(messageResourceGet).not.toHaveBeenCalled();
   });
 });
 
@@ -92,6 +93,18 @@ function mockRuntime(
   };
 }
 
+function fakeBotCli(): FeishuBotCli {
+  return {
+    downloadResource: (request) => writeNewWorkspaceFileNoFollow(
+      request.workspaceRoot,
+      request.workspaceDir,
+      request.workspaceRelativePath,
+      Readable.from([Buffer.from("image bytes")]),
+      request.maxBytes,
+    ),
+  };
+}
+
 function escapeRegExp(value: string): string {
   return value.replace(/[.*+?^${}()|[\]\\]/g, "\\$&");
 }