fix: inline seroval and seroval-plugins in dev SSR

[brenelz]

Problem

With serverFunctions: { components: true } in SSR start mode, a server component that resolves after the shell flushes (for example one that awaits before returning) fails under vite dev:

[SSR_RENDER_ERROR_CONTAINED] Render error in a <Loading> boundary — the fragment rejected and the client re-renders it:
Error: Seroval caught an error during the parsing process.
The value [object Object] of type "object" cannot be parsed/serialized.

The <Loading> boundary contains the error, so the component silently renders only on the client. Production builds are fine.

Cause

Two copies of seroval load in dev SSR:

• The inlined @solidjs/web gets seroval from the module runner, which resolves with the development condition, so it loads dist/dev/index.js.
• seroval-plugins is externalized, so Node loads it and resolves its own import "seroval" without development, which loads dist/index.js.

Seroval detects streams with value instanceof Stream. ReadableStreamPlugin builds its Stream with one copy and the serializer checks it against the other, so the check fails. A server component hits this through its sc:live channel, a ReadableStream serialized into the document. I confirmed the two copies by logging each module evaluation and tracing the rejected value back to sc:live.

This is the same split the plugin already handles for solid-js / @solidjs/web (the comment above the existing inline list describes it).

Fix

Add seroval and seroval-plugins to the dev SSR inline list next to solid-js and @solidjs/web. The existing guards still apply: dev only, Vitest projects and hosts that set noExternal: true are left alone.

Testing

• New config-level test: examples/start-ssr/test/ssr-inline.mjs, in the style of dedupe.mjs, wired into the example's test script. It fails without the fix and passes 4/4 with it. dedupe.mjs still passes 8/8.
• End to end: in an app (Solid rc.14, plugin next.47, Nitro) with an awaiting server component, I swapped in the built dist/esm/index.mjs. With the published plugin the seroval error appears 6 times over 3 requests; with this change it appears 0 times, the component renders in the SSR'd document, and the browser hydrates with no console errors.

The existing frames mode of start-ssr doesn't reproduce the bug: its server components serialize sc:live before the shell flushes. So the new test only checks the config; a runtime regression test would need a server component that resolves after the flush.

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Latest commit: ae8a8b0

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@solidjs/vite-plugin	Patch

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