[v11] Manual test SvelteKit

Greenfield customer-path test for `@sentry/sveltekit` on SDK v11 alpha (`11.0.0-alpha.1` or newer).

**Scaffold:** `sv create`.

Parent: [JS-3386](). Wizard still installs v10 until [WIZARD-139]() — pin `@alpha` after; do not duplicate that ticket.

## Protocol

* App lives **outside** the `sentry-javascript` monorepo
* **pnpm 10**
* Run the wizard, then pin `@sentry/sveltekit@alpha` — **note if the wizard left v10**
* Install clean (peers, hoist, `@sentry/cli` scripts)
* `dev` + `build`/`start`: an **error** and a **trace** in a real Sentry project (personal **free** org is enough — not the employee `sentry` org, not a paid plan)
* No `sendDefaultPii`; `dataCollection` looks right; span streaming on