[adapter-cloudflare] Update static file logic to allow spaces in filenames

[isaac-mcfadyen]

This PR makes the Worker URL-decode any received paths so that static files with spaces in the filename can be found.

Without this change, accessing a static file that has a space in it (for example, https://example.com/Example File.pdf) fails. This is because:

1. The file is added to the ASSETS Set with a space (non-URL encoded).
2. The browser automatically URL encodes any space ( ) characters to %20, as it should.
3. When the request is received by the worker, it looks for a static file in the ASSETS Set with %20 instead of space ( ). This fails, so the request is passed to SvelteKit which replies with a 404.

I've tested this change on my own local copy of adapter-cloudflare in production and it works.

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🦋 Changeset detected

Latest commit: 64c1047

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

This PR includes changesets to release 1 package

Name	Type
@sveltejs/adapter-cloudflare	Patch

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[pngwn]

Lgtm.

[lukeed]

the lint step needs to be fixed, but looks good otherwise

[isaac-mcfadyen]

Sorry! Fixed now.