fix(dev-server): fix loading css error

[khouwdevin]

Hi Takuya-san,

Found another issue: theme CSS isn't loading at all when the dev server starts — comes up completely unstyled.

Turns out Vite needs the /@fs prefix to serve absolute filesystem paths through import() — dev-server.tsx was just concatenating the raw path, which doesn't work. I also tried WSL since the docs suggest that should sidestep path issues, but it failed the same way there too.

Fix:

const normalizedBase = baseProjectPath.replace(/\\/g, '/')
const fsBase = normalizedBase.startsWith('/') ? normalizedBase : `/${normalizedBase}`
const cssFiles = styleSheets.map((ss) => `/@fs${fsBase}/styles/${ss}`)

The normalizedBase step is there to handle Windows paths (backslashes, drive letters) — Unix paths don't need it, but the normalize is harmless either way.

Tested on Windows and WSL, both work now.

[craftzdog]

Thanks! tested it on my mac as well