Fix Windows CI: normalize backslash paths in SCSS/Stylus alias resolution

[Copilot]

path.resolve() and path.join() return backslash-separated paths on Windows. These get interpolated directly into SCSS @use/@import and Stylus @import statements, which the preprocessors cannot resolve.

// Before: @use "C:\tmp\src\styles\tokens" — Sass fails
// After:  @use "C:/tmp/src/styles/tokens" — Sass resolves correctly
finalPath = finalPath.replace(/\\/g, '/')

• Normalize resolved alias paths to forward slashes before inserting into SCSS source in sassCompiler.ts
• Apply the same forward-slash normalization to resolved alias paths in stylusCompiler.ts

Original prompt

---

This section details on the original issue you should resolve

<issue_title>ci windows test failed</issue_title>
<issue_description>ci windows test failed，下面是失败的原因，我猜测可能是windows上一些文件路径的问题

Run nr test

transform-to-unocss@0.1.24-beta.3 test D:\a\transformToUnoCSS\transformToUnoCSS
vitest

RUN v3.2.4 D:/a/transformToUnoCSS/transformToUnoCSS

✓ test/sass-mixed-decls.test.ts (5 tests) 519ms
✓ sassCompiler deprecation warnings fix > should compile SCSS with mixed declarations without warnings 445ms
stdout | test/complex-scss-for-loop.test.ts > Complex SCSS for-loop and variable syntax > should handle SCSS @for loops with variables correctly
Testing complex SCSS with @for loops and variables...
[DEBUG] transformCode started: {"filepath":"complex-scss-test.vue","isJsx":true,"codeLength":3103}
[DEBUG] transformCode detected type: vue, original type: undefined, filepath: complex-scss-test.vue
[DEBUG] transformCode: Processing as Vue file

stdout | test/complex-scss-for-loop.test.ts > Complex SCSS for-loop and variable syntax > should handle SCSS @for loops with variables correctly
[DEBUG] transformVue started: {
"filepath": "complex-scss-test.vue",
"isJsx": true,
"codeLength": 3103
}
[DEBUG] After inline style transformation
[DEBUG] transformMedia: No https://github.com/media queries found

stdout | test/complex-scss-for-loop.test.ts > Complex SCSS for-loop and variable syntax > should handle SCSS @for loops with variables correctly
[DEBUG] Processing styles: {
"stylesCount": 1
}
[transform-to-unocss] Compiling SCSS file: complex-scss-test.vue

stdout | test/complex-scss-for-loop.test.ts > Complex SCSS for-loop and variable syntax > should handle SCSS @for loops with variables correctly
[DEBUG] CSS compiled successfully: {
"styleIndex": 0,
"originalStyleLength": 2221,
"compiledCssLength": 4612,
"scoped": true
}

stdout | test/complex-scss-for-loop.test.ts > Complex SCSS for-loop and variable syntax > should handle SCSS @for loops with variables correctly
[DEBUG] importCss started: {
"filepath": "complex-scss-test.vue",
"styleLength": 4612,
"hasImports": false
}

color: $brand-color;
}
</style>
❯ test/transformAstro.test.ts:57:20
55| })
56|
57| expect(result).toContain('text-red')
| ^
58| expect(result).not.toContain('$brand-color')
59|

⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯[1/1]⎯

Test Files 1 failed | 14 passed (15)
Tests 1 failed | 63 passed (64)
Start at 06:43:33
Duration 6.63s (transform 546ms, setup 0ms, collect 6.36s, tests 6.84s, environment 4ms, prepare 2.21s)

Error: AssertionError: expected '---\nexport const prerender = true;\n…' to contain 'text-red'

Expected
Received
text-red
export const prerender = true;
hi

<style> @use "@/styles/tokens" as *; .title { color: $brand-color; } </style>

❯ test/transformAstro.test.ts:57:20

 ELIFECYCLE  Test failed. See above for more details.
Error: Process completed with exit code 1.</issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes ci windows test failed #68

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[Simon-He95]

@copilot 这个路径只是我的猜测，另外你这个修复方法好吗

[Copilot]

@copilot 这个路径只是我的猜测，另外你这个修复方法好吗

你的猜测是对的，确实是 Windows 路径问题。根本原因：在 sassCompiler.ts 的 replaceAliasImports 中，path.resolve() 在 Windows 上返回反斜杠路径（如 C:\tmp\src\styles\tokens），这些路径被直接插入到 SCSS @use 语句中。Sass 无法解析反斜杠路径，导致编译失败并回退返回原始 CSS（$brand-color 未解析）。

修复方法是在将路径插入 SCSS 源码之前，用 finalPath.replace(/\\/g, '/') 将反斜杠转换为正斜杠。这是业界标准做法（Vite 的 normalizePath、npm 的 slash 包等都用同样的方式）。Sass 在所有平台上都能正确解析正斜杠路径。

在 5069899 中还修复了 stylusCompiler.ts 中同样的问题。