feat(watcher): gate receipt watch with WATCHER_MAILBOXES

Limit Pub/Sub INBOX watch and receipt processing to an allowlisted mailbox set; leave the agent CLI usable for all connected accounts.

Co-authored-by: Cursor <cursoragent@cursor.com>

apps/watcher/test/watcher-mailboxes.test.js

@@ -0,0 +1,46 @@
+import assert from "node:assert/strict";
+import { describe, it } from "node:test";
+import {
+  isWatcherMailboxAllowed,
+  parseWatcherMailboxes,
+} from "../src/config.js";
+
+describe("parseWatcherMailboxes", () => {
+  it("returns empty set for blank input", () => {
+    assert.equal(parseWatcherMailboxes("").size, 0);
+    assert.equal(parseWatcherMailboxes(null).size, 0);
+    assert.equal(parseWatcherMailboxes("  ,  ").size, 0);
+  });
+
+  it("normalizes and splits emails", () => {
+    const set = parseWatcherMailboxes(
+      " Eleven16th@gmail.com , other@Example.COM ",
+    );
+    assert.deepEqual([...set].sort(), [
+      "eleven16th@gmail.com",
+      "other@example.com",
+    ]);
+  });
+});
+
+describe("isWatcherMailboxAllowed", () => {
+  it("allows all when allowlist is empty", () => {
+    const empty = new Set();
+    assert.equal(isWatcherMailboxAllowed("anyone@x.com", empty), true);
+    assert.equal(isWatcherMailboxAllowed(null, empty), true);
+  });
+
+  it("requires membership when allowlist is set", () => {
+    const allow = parseWatcherMailboxes("eleven16th@gmail.com");
+    assert.equal(
+      isWatcherMailboxAllowed("eleven16th@gmail.com", allow),
+      true,
+    );
+    assert.equal(
+      isWatcherMailboxAllowed("Eleven16th@Gmail.com", allow),
+      true,
+    );
+    assert.equal(isWatcherMailboxAllowed("other@gmail.com", allow), false);
+    assert.equal(isWatcherMailboxAllowed(null, allow), false);
+  });
+});