examples/linear: playwright webServer port mismatch (expects 3001, vtz dev defaults to 3000)

[viniciusdacal]

Description

`examples/linear/playwright.config.ts` waits on `http://localhost:3001\`:

```ts
webServer: {
command: 'bun run dev',
url: 'http://localhost:3001',
...
}
```

But `examples/linear/package.json` defines:

```json
"dev": "vtz dev"
```

`vtz dev` defaults to port 3000, so playwright never gets a 200 from `:3001` and times out after 30s with `Error: Timed out waiting 30000ms from config.webServer`.

Fix

Two options — pick one:

A) Update the dev script to bind 3001 (recommended, isolates linear from other examples that use 3000):
```json
"dev": "vtz dev --port 3001"
```

B) Update the playwright config to wait on 3000:
```ts
url: 'http://localhost:3000'
```

Option A is cleaner since `entity-todo` already uses 3000 and these two examples might run side-by-side.

Acceptance Criteria

• `cd examples/linear && npx playwright test` boots its webServer without timeout.
• `linear/e2e/linear.spec.ts` reaches the test body (passes or fails based on app behavior, not on webServer timeout).
• No port collision when running `linear` and `entity-todo` e2e at the same time.

[viniciusdacal]

Fixed by #3010 (which closed the duplicate #3007). examples/linear/package.json's dev script is now vtz dev --port 3001, matching playwright.config.ts and e2e/linear.spec.ts. Verified locally: vtz dev --port 3001 boots on 3001 and returns 200 — no webServer timeout. linear (3001) and entity-todo (3000) no longer collide.