run-adapter-static also creates dynamic directories names as static folders

[Jack5079]

https://github.com/Jack5079/marko-slug-bug

<!-- +page.marko -->
<a href="/path">path</a>
<!-- $+page.marko -->
<h1>here be $</h1>

Results in

dist
├── $
│   └── index.html
├── 404
│   └── index.html
├── path
│   └── index.html
└── index.html

But it should be:

dist
├── 404
│   └── index.html
├── path
│   └── index.html
└── index.html

[DylanPiercey]

Good catch @Jack5079, I think we need to add some more checks here https://github.com/marko-js/run/blob/main/packages/adapters/static/src/index.ts#L86

Will try to get to it once I have a sec. If you want to take a stab at a PR that'd be great also 🙏