wrapFetchWithSentry quote scan breaks across chunks

`wrapFetchWithSentry` rewrites the HTML response stream chunk-by-chunk to inject trace meta tags. The quote-scanning path in `addMetaTagToHead` is not sound across chunk boundaries, and a partner integration hit a build-breaking TanStack prerender failure that is separate from the already-fixed React #418 newline issue.

Reported by a Cloudflare + TanStack Start partner integration. Observed on `@sentry/cloudflare` / related stack at `10.56.0`. The reporter confirmed the React hydration #418 half matches #21915 (fixed in `10.64.0`); this tracks the remaining stream-transform failure.

**Verified**
- On current `develop`, `packages/tanstackstart-react/src/server/wrapFetchWithSentry.ts` still processes each decoded chunk independently with:
```ts
// Skip quoted attribute values so we don't match inside e.g. data-code="......"
return htmlChunk.replace(/"[^"]*"|'[^']*'|()/g, ...)
```
- The same file still documents an optimistic assumption that HTML chunks will not split inside ``; if they do, injection is skipped rather than carried across chunks.
- Related closed issues do **not** cover this failure mode:
- #21915 — newline in `getTraceMetaTags` caused React #418 (fixed in `10.64.0` via #22004)
- #23305 — UTF-8 multi-byte characters corrupted across stream chunks in React Router injectors

**Reported symptoms**
- TanStack SSR stream transform threw `SSR stream tail exceeded maximum buffer` during prerender and failed the build
- Failure was timing/chunk-boundary dependent: passed locally, failed in CI
- Partner hypothesis (medium confidence): a chunk boundary inside a quoted attribute value can desynchronize the per-chunk quote scan and misparse markup, independent of the newline fix

**Workaround**
- Omit `wrapFetchWithSentry` when tracing is not needed (`tracesSampleRate: 0`); middleware-only setup was sufficient for the reporter
- Bump to `>=10.64.0` for the separate #418 newline fix, then re-test the wrapper if tracing is enabled

**Unknown**
- Exact TanStack Start / React versions in the failing app
- Minimal public reproduction
- Whether the buffer error is caused only by quote-scan desync, by `` split across chunks, by interaction with TanStack prerender buffering, or a combination

Requested by **Nicolas Hrubec**.

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