perf: merge client chunks based on server page usage (#1653)

This PR enables client reference chunk optimization implemented by
vitejs/vite-plugin-react#766 and
vitejs/vite-plugin-react#767. I will likely
enables this by default in next release, but testing on Waku for
starter.

The idea is similar to the one explained in
https://devongovett.me/blog/parcel-rsc.html "Bundling client components"
section.
> One interesting thing you might notice is that "use client" is not an
explicit code splitting point like dynamic import(). If you import more
than one client component from a server component, the client components
will be grouped together into a single bundle instead of split into
separate bundles.

This difference can be seen in `packages/website` where previously each
`"use client"` component file becoming its own chunk e.g.
https://waku.gg/

- `Destination` -> `/assets/destination-xxx.js`
- `Start` -> `/assets/start-xxx.js`
- `Fade` -> `/assets/fade-xxx.js`
- `Menu` -> `/assets/menu-xxx.js`
- `Navigation` -> ...
- `Scroll` -> ...
- etc.

but now, some client component chunks are merged together based on
server-side usage, e.g.

https://waku-git-fork-hi-ogawa-08-24-featoptimi-f784e4-daishis-projects.vercel.app/

- `Destination`, `Start` ->  `/assets/index-xxx.js` (only used in `/`)
- `Fade`, `Menu`, `Navigation`, `Scroll` -> `/assets/fade-xxx.js`
(shared by all pages `/`, `/blog`, ...)
- etc.

---------

Co-authored-by: Daishi Kato <[email protected]>

Author: hi-ogawa

packages/waku/package.json

@@ -81,7 +81,7 @@
     "@hono/node-server": "1.19.0",
     "@swc/core": "1.13.4",
     "@vitejs/plugin-react": "5.0.1",
-    "@vitejs/plugin-rsc": "0.4.22",
+    "@vitejs/plugin-rsc": "0.4.25",
     "dotenv": "17.2.1",
     "hono": "4.9.4",
     "rsc-html-stream": "0.0.7",

packages/waku/src/lib/vite-rsc/plugin.ts

@@ -96,6 +96,7 @@ export function rscPlugin(rscPluginOptions?: RscPluginOptions): PluginOption {
       keepUseCientProxy: true,
       ignoredPackageWarnings: [/.*/],
       useBuildAppHook: true,
+      clientChunks: (meta) => meta.serverChunk,
     }),
     {
       name: 'rsc:waku',