Fix Sass fallback and zip finalization

Ensure sass-loader receives correct implementation by using mod.default || mod when falling back to 'sass'. Resolve zip completion on 'finish' and handle errors via stream events to avoid truncated archives.

Author: PeterDaveHello

build.mjs

@@ -87,17 +87,13 @@ async function runWebpack(isWithoutKatex, isWithoutTiktoken, minimal, sourceBuil
   ]
   if (isWithoutKatex) shared.push('./src/components')
 
-  // Use the default export from sass-embedded; sass-loader expects the implementation object.
-  // Fallback to `sass` if sass-embedded is unavailable.
   let sassImpl
   try {
     const mod = await import('sass-embedded')
     sassImpl = mod.default || mod
   } catch (e) {
     const mod = await import('sass')
-    // Prefer namespace import style to avoid deprecated default import warning
-    // "import sass from 'sass'" is deprecated; use namespace instead
-    sassImpl = mod
+    sassImpl = mod.default || mod
   }
 
   const dirKey = path.basename(sourceBuildDir || outdir)
@@ -426,14 +422,10 @@ async function zipFolder(dir) {
     const onError = (err) => reject(err)
     output.on('error', onError)
     archive.on('error', onError)
-    output.on('close', resolve)
+    output.on('finish', resolve)
     archive.pipe(output)
     archive.directory(dir, false)
-    try {
-      archive.finalize()
-    } catch (err) {
-      onError(err)
-    }
+    archive.finalize()
   })
 }