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Fix react-pdf regression by disabling compression

Client-side PDF generation hangs indefinitely (no error) in Firefox when
rendering runs in a web worker. The stream's 'end' event and its final
'data' chunks never arrive, so toBlob() never resolves.

Root cause: react-pdf compresses each PDF object through an async
zlib.createDeflate() stream, and the document only finishes once every
deflate stream has emitted 'end' (its _waiting counter reaches 0). That
whole completion chain rides on pdfkit's bundled process/browser nextTick
polyfill, i.e. setTimeout(0). On a cold HTTP cache the first render's
network fetches race that setTimeout(0) cascade in the Firefox worker and
it stalls at the tail, so the last deflate streams never complete.

The trigger is cold-start timing, not document size: any completed render
cures the session, the cure survives a normal reload (F5) but returns on a
hard reload (Ctrl+F5, cold cache). It reproduces in staging, and only in
Firefox web workers. The mechanism is unchanged between @react-pdf/pdfkit
4.x and 5.x; the recent upgrade merely started tripping a pre-existing
fragility.

Disabling compression bypasses the deflate streams entirely: object bodies
are written synchronously and finalize() runs synchronously from end(), so
completion no longer depends on the setTimeout(0) scheduler. This removes
the racing mechanism rather than masking the missing event. Trade-off is
larger PDF files; acceptable until the scheduler issue is fixed upstream.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

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