fix: detect Node via process.type to keep Electron main process working

[claygeo]

Follow-up to #951 (thanks for merging that one!) and #813.

#951 fixed the Electron renderer crash by adding !process.versions.electron to IN_NODE. While verifying it I noticed that guard also flips IN_NODE to false in the Electron main and utility processes, because process.versions.electron is set in every Electron process, not just the renderer. Those are real Node environments, so PGlite then takes the browser path and loses the Node.js fs code path it needs. Running PGlite in the main process for filesystem-backed storage (keeping DB access out of the renderer) is a common pattern, so this is a regression.

This keys the check off process.type instead, which cleanly separates Electron's web contexts from its Node ones:

Environment	process.type	!process.versions.electron (#951)	process.type exclusion (this PR)
Plain Node	undefined	Node ✅	Node ✅
Node worker_threads	undefined	Node ✅	Node ✅
Electron main	browser	browser ❌	Node ✅
Electron utility	utility	browser ❌	Node ✅
Electron renderer	renderer	browser ✅	browser ✅
Electron renderer web worker	worker	browser ✅	browser ✅
Electron renderer service worker	service-worker	browser ✅	browser ✅
Browser (no process)	n/a	browser ✅	browser ✅

So it still fixes the original renderer crash from #813, and additionally keeps the Node path working in the Electron main and utility processes.

process.type is Electron specific and not in @types/node, hence the small structural cast.

Checks run locally: typecheck, lint, and build pass for @electric-sql/pglite-utils. Changeset included (patch to @electric-sql/pglite).