This is a comment left during a code review.
Path: src/browser/server-context.selection.ts
Line: 41-44

Comment:
**Deadline check precedes sleep — loop can overrun by one interval**

The `while` condition evaluates `Date.now() < deadlineAt` *before* the 200 ms `setTimeout` and the subsequent `listTabs()` call. This means the last iteration can start with only 1 ms remaining on the deadline, sleep 200 ms, call `listTabs()`, and resolve up to ~200 ms + network time *past* the 3 s deadline before the throw is reached. In most cases the overrun is harmless, but it slightly weakens the "fail within 3 s" guarantee.

A common fix is to also check the deadline after waking, or to measure elapsed time with an `AbortSignal`/`clearTimeout` pattern. As a minimal fix, moving the deadline check to after the sleep would ensure the timeout is observed more faithfully:

```suggestion
          while (tabs1.length === 0) {
            await new Promise((resolve) => setTimeout(resolve, 200));
            if (Date.now() >= deadlineAt) break;
            tabs1 = await listTabs();
          }
```

How can I resolve this? If you propose a fix, please make it concise.

This is a comment left during a code review.
Path: src/browser/server-context.ensure-tab-available.prefers-last-target.test.ts
Line: 126-153

Comment:
**Deadline-exceeded path is not tested**

The new test only covers the happy path (tabs reappear within one polling interval). The complementary case — `lastTargetId` is set, `/json/list` stays empty throughout the 3 s window, and `ensureTabAvailable` must still throw with the "no attached Chrome tabs" message — has no automated test.

This is the code path the PR description says "was not verified end-to-end," and it's also the path that ensures the retry doesn't silently swallow the error on a genuinely broken relay. A test like the one below would complete near-instantly with fake timers:

```ts
it("throws after deadline when extension tabs never reappear (lastTargetId set)", async () => {
  vi.useFakeTimers();
  try {
    // Provide enough empty responses to cover the retry window plus one first call
    const responses = [
      [{ id: "A", type: "page", url: "https://a.example", webSocketDebuggerUrl: "ws://x/a" }],
      [{ id: "A", type: "page", url: "https://a.example", webSocketDebuggerUrl: "ws://x/a" }],
      // All subsequent polls return empty
      ...Array(20).fill([]),
    ];
    stubChromeJsonList(responses);
    const state = makeBrowserState();
    const ctx = createBrowserRouteContext({ getState: () => state });
    const chrome = ctx.forProfile("chrome");
    await chrome.ensureTabAvailable(); // sets lastTargetId = "A"

    const failPromise = chrome.ensureTabAvailable();
    await vi.advanceTimersByTimeAsync(4_000); // past the 3 s deadline
    await expect(failPromise).rejects.toThrow(/no attached Chrome tabs/i);
  } finally {
    vi.useRealTimers();
  }
});
```

How can I resolve this? If you propose a fix, please make it concise.