remove Vite static asset middleware

[Rich-Harris]

Noticed in #1634 (and I can't believe this hasn't come up sooner) that Vite will serve assets in the static folder, with that prefix — so /favicon.png can also be requested as /static/favicon.png.

Fixed by removing viteServeStaticMiddleware in the plugin (which, aside: this feels like a massive code smell and an indication that the design of the Vite dev server isn't optimal for the SSR framework use case).

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[Conduitry]

I'm not completely clear on what this new approach is doing, but the changeset and the test description should probably be updated.

[Rich-Harris]

updated those descriptions

[benmccann]

Could you explain why this was changed? The last iteration made sense to me whereas this iteration does not

[Rich-Harris]

The static middleware is needed to serve things like image files in src

[istarkov]

Seems like this breaks assets imported as urls used in development mode, i.e before

import myimage from '../../static/myimage.png?url';
...
<img src={myimage} />

worked in dev mode under /static/myimage.png path, now its not. (no issues with prod)