QRL chunks fail to load on cold Vite dev SSR requests (beta.35 + Vite 8) — `TypeError: Importing a module script failed` + 504 Outdated Optimize Dep

### Which area(s) are affected?

`Qwik Runtime`, `Rollup / Vite plugin`

### Describe the bug

In Vite dev SSR (`pnpm dev`), the first request to a route that uses `useVisibleTask$` produces `TypeError: Importing a module script failed` on multiple QRL chunks. Subsequent requests succeed.

```
qrl WebVitals_component_useVisibleTask_yn4FTDO7PRs failed to load TypeError: Importing a module script failed.
qrl Link_component_useVisibleTask_xKeuRmnoNSA failed to load TypeError: Importing a module script failed.
qrl PWAProvider_component_useVisibleTask_PiqqFnaN19Y failed to load TypeError: Importing a module script failed.
```

Often accompanied by a `504 (Outdated Optimize Dep)` from Vite for one of the requested chunks:

```
Failed to load resource: the server responded with a status of 504 (Outdated Optimize Dep)
```

The pattern looks like Vite's dep-optimization invalidating chunk URLs mid-request: the page renders, qwikloader starts importing QRL chunks, Vite re-optimizes and changes the chunk hashes, the in-flight imports point at stale URLs and 504.

History across versions:

- **beta.32:** Present but invisible — qwikloader handled the failure gracefully.
- **beta.34:** Became deterministic, broke pages outright. We held at beta.32 for two release cycles.
- **beta.35:** PR #8606 (skip preloader in dev) reduced it to a one-retry flake under Playwright. Shipped, but still visible on cold loads.

**Production builds are unaffected** — only Vite dev SSR.

### Reproduction

I don't have a self-contained min-repro yet. The flake appears tied to overall project complexity / dependency-graph size and may not surface in a trimmed-down project. Filing this with embedded evidence and willing to construct a min-repro if a maintainer can suggest what scale of components / cold-load conditions to target.

**What our setup looks like** (private codebase, so I can't link it):
- ~6 components using `useVisibleTask$` near the entry route (`/auth/sign-in`)
- Cloudflare-Workers SSR adapter, Vite dev for local
- Playwright cold-loads in WebKit (`mobile-webkit` project) and Chromium

**Symptom timing on cold load:**
1. First request: 15–17 s wall time, `Importing a module script failed` on 2–4 QRL chunks, page errors in console (functionality not necessarily broken, but tests checking `errors.toEqual([])` fail).
2. Retry: 1.5–3.5 s, succeeds cleanly.

If we re-enable Qwik's built-in `qwikLoader: "module"` (default), qwikloader itself joins the failed-chunk set and interactivity breaks deterministically on Chromium (`market-explorer: navigate to detail`, `portfolio-grid: search filters` failed even after 2 retries).

### Steps to reproduce

Approximate — minimum complexity to surface this isn't established yet:
1. Qwik app with multiple `useVisibleTask$` components active on entry route.
2. `pnpm dev` (Vite dev SSR, not built).
3. Cold-load entry route in Playwright WebKit, capture `console.error`.
4. Expect: empty error list. Observed: 2–4 `Importing a module script failed` errors.
5. Reload: clean.

### System Info

```
System:
  OS: macOS 26.5 (Apple Silicon, Apple M5 Pro)
  Shell: zsh 5.9
Binaries:
  Node: 22.22.2
  pnpm: 10.33.2
Browsers (also confirmed in Playwright Linux Ubuntu CI):
  Safari: 26.5
  Chrome: 148.0.7778.97
npmPackages:
  @qwik.dev/core: 2.0.0-beta.35
  @qwik.dev/router: 2.0.0-beta.35
  @playwright/test: 1.60.0
  vite: 8.0.13
```

CI environment where the same pattern reproduces: Ubuntu 24.04, Node 22, fresh `pnpm dev`, Playwright `mobile-webkit` against `http://localhost:3000`.

### Additional Information

**Workaround that's load-bearing for us today** — removing it deterministically breaks interactivity:

```ts
// entry.ssr.tsx
return renderToStream(<Root />, {
  ...opts,
  qwikLoader: "never",       // skip Qwik's built-in qwikloader emission
  manifest,
});
```

```tsx
// root.tsx
<head>
  {/* ... */}
  <script src="/qwikloader.js" async />    {/* non-module static asset */}
</head>
```

`/qwikloader.js` is a hand-copy of `node_modules/@qwik.dev/core/dist/qwikloader.js` wrapped in an IIFE, served as a non-module script. This bypasses Vite's dev module resolver entirely.

**Hypothesis:** Vite's dep-optimization cache for SSR is invalidating chunk URLs mid-import during cold requests, and Qwik's QRL loader doesn't tolerate the `504 Outdated Optimize Dep` response. The non-module static loader works because Vite doesn't intercept non-module `<script>` tags.

Happy to build a minimal repro, capture HAR + Vite dep-cache state during a cold request, or run targeted experiments (e.g., disable `optimizeDeps`, vary number of `useVisibleTask$` components) if useful.


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QRL chunks fail to load on cold Vite dev SSR requests (beta.35 + Vite 8) — `TypeError: Importing a module script failed` + 504 Outdated Optimize Dep #8634

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QRL chunks fail to load on cold Vite dev SSR requests (beta.35 + Vite 8) — TypeError: Importing a module script failed + 504 Outdated Optimize Dep #8634

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QRL chunks fail to load on cold Vite dev SSR requests (beta.35 + Vite 8) — `TypeError: Importing a module script failed` + 504 Outdated Optimize Dep #8634