Fix virtual specifiers starting with /@ not being supported

[marvinhagemeister]

There is rollup-plugin-windicss which has chosen a virtual identifier that includes a leading slash /@windicss/windi.css this is very unfortunate as that character normally means "resolve from the public dir" in our case since we view it through the lens of a webserver.

To workaround that I've added a special case for urls where the leading slash is immediately followed by an at sign /@.

Fixes #811

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🦋 Changeset detected

Latest commit: f03859b

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
wmr	Patch

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[github-actions]

Size Change: +54 B (0%)

Total Size: 796 kB

Filename	Size	Change
packages/wmr/wmr.cjs	758 kB	+54 B (0%)

ℹ️ View Unchanged

Filename	Size
examples/demo/dist/about/index.html	713 B
examples/demo/dist/alias-outside/index.html	692 B
examples/demo/dist/assets/Calendar.********.css	702 B
examples/demo/dist/assets/style.********.css	624 B
examples/demo/dist/chunks/alias-outside.********.js	137 B
examples/demo/dist/chunks/class-fields.********.js	211 B
examples/demo/dist/chunks/compat.********.js	15.3 kB
examples/demo/dist/chunks/hoofd.module.********.js	1.47 kB
examples/demo/dist/chunks/index.********.js	303 B
examples/demo/dist/chunks/json.********.js	238 B
examples/demo/dist/chunks/meta-tags.********.js	299 B
examples/demo/dist/chunks/prerender.********.js	2.44 kB
examples/demo/dist/class-fields/index.html	703 B
examples/demo/dist/compat/index.html	1.6 kB
examples/demo/dist/env/index.html	779 B
examples/demo/dist/error/index.html	708 B
examples/demo/dist/files/index.html	738 B
examples/demo/dist/index.********.js	7.66 kB
examples/demo/dist/index.html	770 B
examples/demo/dist/json/index.html	711 B
examples/demo/dist/lazy-and-late/index.html	714 B
examples/demo/dist/meta-tags/index.html	781 B

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