refactor: daemon internals, and fix a leak the merge exposed

IdMultiplexer and EventRouter were the only classes in src/; they are now
createIdMultiplexer/createEventRouter closures like every other factory
here. The multiplexer kept {clientId, localId} per daemon id while the
bridge kept {send, clientId, localId, timer, isAttach} under the same key
— two maps of overlapping data, and mux.resolve()'s return value was
discarded at three of four call sites. One map now holds the union.

That merge fixes a real leak: removeClient cleared the multiplexer but
never the callbacks map, so a disconnected client's timers stayed armed
and later fired a response at a socket that was gone. clearClient now
cancels them, and a test pins it.

handleRequest polled every 250ms for up to 15s per request when Chrome
was down; N queued requests now await one connect signal.

server.ts uses its own protocol's serialize/deserialize instead of
hand-rolled JSON, and broadcast no longer routes through `this` — the
only `this` in the codebase, and the one thing that breaks when the
server object is destructured.

cdp/event-queue.ts held two unrelated concerns; the request/timeout half
moves to cdp/pending-requests.ts. cdp/daemon-transport.ts is the client
half of the daemon protocol, so it moves to daemon/transport.ts.

test/daemon/ needs adding to the test glob to run at all — there was no
daemon test directory before because none of this was reachable without
live Chrome.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

7 files changed, 138 insertions, 6 deletions

diff --git a/test/cdp/event-queue-test.ts b/test/cdp/event-queue-test.ts
index cae8143..771ce8e 100644
--- a/test/cdp/event-queue-test.ts
+++ b/test/cdp/event-queue-test.ts
@@ -1,6 +1,7 @@
 import { test, describe } from "node:test";
 import assert from "node:assert/strict";
-import { makeEventQueue, rejectAllPending, sendWithTimeout, type Pending } from "../../src/cdp/event-queue";
+import { makeEventQueue } from "../../src/cdp/event-queue";
+import { rejectAllPending, sendWithTimeout, type Pending } from "../../src/cdp/pending-requests";
 
 describe("event queue iteration", () => {
   test("yields pushed events in order", async () => {
diff --git a/test/daemon/bridge-routing-test.ts b/test/daemon/bridge-routing-test.ts
new file mode 100644
index 0000000..7c96bad
--- /dev/null
+++ b/test/daemon/bridge-routing-test.ts
@@ -0,0 +1,131 @@
+import { test, describe } from "node:test";
+import assert from "node:assert/strict";
+import { createEventRouter, createIdMultiplexer, type InFlight } from "../../src/daemon/bridge";
+import type { SendToClient } from "../../src/daemon/bridge";
+import type { WireEvent } from "../../src/daemon/protocol";
+
+const noSend: SendToClient = () => {};
+const entry = (clientId: string, localId: number): Omit<InFlight, "timer"> => ({
+  clientId,
+  localId,
+  send: noSend,
+  isAttach: false,
+});
+
+const inertTimer = (): ReturnType<typeof setTimeout> => setTimeout(() => {}, 60_000);
+
+describe("daemon id multiplexer", () => {
+  test("two clients using the same local id get distinct daemon ids", () => {
+    const mux = createIdMultiplexer();
+    const a = mux.allocate(entry("client-a", 1), inertTimer);
+    const b = mux.allocate(entry("client-b", 1), inertTimer);
+    assert.notEqual(a, b);
+  });
+
+  test("a response is routed back to the client that asked, with its own id", () => {
+    const mux = createIdMultiplexer();
+    const a = mux.allocate(entry("client-a", 7), inertTimer);
+    const b = mux.allocate(entry("client-b", 7), inertTimer);
+    assert.equal(mux.take(b)?.clientId, "client-b");
+    const takenA = mux.take(a);
+    assert.equal(takenA?.clientId, "client-a");
+    assert.equal(takenA?.localId, 7);
+  });
+
+  test("taking the same daemon id twice yields nothing the second time", () => {
+    const mux = createIdMultiplexer();
+    const id = mux.allocate(entry("client-a", 1), inertTimer);
+    assert.ok(mux.take(id));
+    assert.equal(mux.take(id), undefined);
+  });
+
+  test("an unknown daemon id is not mistaken for an in-flight request", () => {
+    const mux = createIdMultiplexer();
+    assert.equal(mux.take(999), undefined);
+  });
+
+  test("clearClient drops only that client's in-flight requests", () => {
+    const mux = createIdMultiplexer();
+    const a = mux.allocate(entry("client-a", 1), inertTimer);
+    const b = mux.allocate(entry("client-b", 1), inertTimer);
+    mux.clearClient("client-a");
+    assert.equal(mux.take(a), undefined);
+    assert.equal(mux.take(b)?.clientId, "client-b");
+  });
+
+  test("clearClient cancels the pending timeout so a gone client is never answered", () => {
+    const mux = createIdMultiplexer();
+    let fired = false;
+    mux.allocate(entry("client-a", 1), () => setTimeout(() => { fired = true; }, 1));
+    mux.clearClient("client-a");
+    return new Promise<void>((resolve) => setTimeout(() => {
+      assert.equal(fired, false);
+      resolve();
+    }, 30));
+  });
+
+  test("takeAll drains every in-flight request exactly once", () => {
+    const mux = createIdMultiplexer();
+    mux.allocate(entry("client-a", 1), inertTimer);
+    mux.allocate(entry("client-b", 2), inertTimer);
+    assert.equal(mux.takeAll().length, 2);
+    assert.equal(mux.takeAll().length, 0);
+  });
+});
+
+const ev = (sessionId?: string): WireEvent => ({
+  type: "event",
+  method: "Page.loadEventFired",
+  ...(sessionId !== undefined ? { sessionId } : {}),
+});
+
+describe("daemon event router", () => {
+  test("a session-scoped event goes only to the client owning that session", () => {
+    const router = createEventRouter();
+    router.record("client-a", "S1");
+    router.record("client-b", "S2");
+    assert.deepEqual(router.route(ev("S1")), ["client-a"]);
+    assert.deepEqual(router.route(ev("S2")), ["client-b"]);
+  });
+
+  test("an event for an unknown session goes nowhere rather than to everyone", () => {
+    const router = createEventRouter();
+    router.record("client-a", "S1");
+    assert.deepEqual(router.route(ev("S9")), []);
+  });
+
+  test("a session-less event goes to every client that holds a session", () => {
+    const router = createEventRouter();
+    router.record("client-a", "S1");
+    router.record("client-b", "S2");
+    assert.deepEqual(router.route(ev()).sort(), ["client-a", "client-b"]);
+  });
+
+  test("re-recording a session moves ownership and does not leave it with the old client", () => {
+    const router = createEventRouter();
+    router.record("client-a", "S1");
+    router.record("client-b", "S1");
+    assert.equal(router.getOwner("S1"), "client-b");
+    assert.deepEqual(router.route(ev("S1")), ["client-b"]);
+  });
+
+  test("releasing a session leaves its events unrouted", () => {
+    const router = createEventRouter();
+    router.record("client-a", "S1");
+    router.release("S1");
+    assert.equal(router.getOwner("S1"), undefined);
+    assert.deepEqual(router.route(ev("S1")), []);
+  });
+
+  test("removing a client releases every session it owned", () => {
+    const router = createEventRouter();
+    router.record("client-a", "S1");
+    router.record("client-a", "S2");
+    router.record("client-b", "S3");
+    router.removeClient("client-a");
+    assert.equal(router.getOwner("S1"), undefined);
+    assert.equal(router.getOwner("S2"), undefined);
+    assert.equal(router.getOwner("S3"), "client-b");
+    assert.deepEqual(router.route(ev()), ["client-b"]);
+  });
+});
diff --git a/test/manual/daemon-transport-test.ts b/test/manual/daemon-transport-test.ts
index 5738e23..30f5a29 100644
--- a/test/manual/daemon-transport-test.ts
+++ b/test/manual/daemon-transport-test.ts
@@ -1,5 +1,5 @@
 import { createIpcServer } from "../../src/daemon/server";
-import { createDaemonTransport } from "../../src/cdp/daemon-transport";
+import { createDaemonTransport } from "../../src/daemon/transport";
 import { DAEMON_SOCKET_PATH } from "../../src/daemon/protocol";
 import type { WireMessage } from "../../src/daemon/protocol";
 import { unlinkSync } from "node:fs";
diff --git a/test/manual/e2e-test.ts b/test/manual/e2e-test.ts
index 81cb4df..02e04a4 100644
--- a/test/manual/e2e-test.ts
+++ b/test/manual/e2e-test.ts
@@ -1,6 +1,6 @@
 import { createIpcServer } from "../../src/daemon/server";
 import { createCdpBridge, type SendToClient } from "../../src/daemon/bridge";
-import { createDaemonTransport } from "../../src/cdp/daemon-transport";
+import { createDaemonTransport } from "../../src/daemon/transport";
 import { DAEMON_SOCKET_PATH } from "../../src/daemon/protocol";
 import type { WireRequest } from "../../src/daemon/protocol";
 import { unlinkSync } from "node:fs";
diff --git a/test/manual/forms-test.ts b/test/manual/forms-test.ts
index 43b2863..274f039 100644
--- a/test/manual/forms-test.ts
+++ b/test/manual/forms-test.ts
@@ -1,4 +1,4 @@
-import { createDaemonTransport } from "../../src/cdp/daemon-transport";
+import { createDaemonTransport } from "../../src/daemon/transport";
 import { createBrowserClient } from "../../src/client";
 import { fillTool, selectOptionTool, setCheckedTool } from "../../src/domains/form";
 import { fillFormTool } from "../../src/domains/form-batch";
diff --git a/test/manual/live-daemon-test.ts b/test/manual/live-daemon-test.ts
index 28ec7cd..5334cbc 100644
--- a/test/manual/live-daemon-test.ts
+++ b/test/manual/live-daemon-test.ts
@@ -1,4 +1,4 @@
-import { createDaemonTransport } from "../../src/cdp/daemon-transport";
+import { createDaemonTransport } from "../../src/daemon/transport";
 
 async function main() {
   const t = createDaemonTransport("pi-live-test");
diff --git a/test/manual/profile-concurrency-test.ts b/test/manual/profile-concurrency-test.ts
index 43cb880..83b233d 100644
--- a/test/manual/profile-concurrency-test.ts
+++ b/test/manual/profile-concurrency-test.ts
@@ -3,7 +3,7 @@ import { existsSync, mkdtempSync, rmSync } from "node:fs";
 import { tmpdir } from "node:os";
 import { join } from "node:path";
 import { createBrowserClient } from "../../src/client";
-import { createDaemonTransport } from "../../src/cdp/daemon-transport";
+import { createDaemonTransport } from "../../src/daemon/transport";
 import { isDaemonRunning, spawnDaemon } from "../../src/daemon/spawn";
 import { closeIsolatedTab, openIsolatedTab } from "../../src/domains/isolated-tab";