修复了在Windows上使用Web访问出现找不到/tmp文件的错误，现在全部都流式放到内存当中了。

并且支持本地自签名部署了

web/src/App.tsx

@@ -13,8 +13,10 @@ export default function App() {
   const [outputHandle, setOutputHandle] = useState<any>(null)
   const [fileItems, setFileItems] = useState<FileItem[]>([])
   const [converting, setConverting] = useState(false)
+  const [concurrency, setConcurrency] = useState(3)
   const [progress, setProgress] = useState({ done: 0, total: 0 })
   const abortRef = useRef(false)
+  const doneCountRef = useRef(0)
 
   useEffect(() => {
     if (isWasmSupported()) {
@@ -47,78 +49,97 @@ export default function App() {
     setOutputHandle(handle)
   }, [])
 
+  const processOne = useCallback(async (
+    entry: { file: File; name: string },
+    idx: number,
+    updateStatus: (status: FileItem['status'], extra?: Partial<FileItem>) => void
+  ) => {
+    if (abortRef.current) return
+
+    try {
+      updateStatus('converting')
+      const buf = await entry.file.arrayBuffer()
+      const result = await convertNcm(buf)
+      let audio = result.data
+
+      let coverData: Uint8Array | undefined
+      if (result.coverUrl) {
+        updateStatus('fetching_cover')
+        try {
+          const resp = await fetch(result.coverUrl)
+          if (resp.ok) {
+            const coverBuf = await resp.arrayBuffer()
+            coverData = new Uint8Array(coverBuf)
+          }
+        } catch {
+          // proceed without cover
+        }
+      }
+
+      updateStatus('writing')
+      if (result.title || result.artist || result.album || coverData) {
+        audio = await embedMetadata(
+          audio,
+          result.format,
+          { title: result.title, artist: result.artist, album: result.album },
+          coverData
+        )
+      }
+
+      const base = entry.name.replace(/\.ncm$/i, '')
+      const outName = `${base}.${result.format}`
+
+      const fileHandle = await outputHandle.getFileHandle(outName, { create: true })
+      const writable = await fileHandle.createWritable()
+      await writable.write(audio)
+      await writable.close()
+
+      updateStatus('done', { format: result.format })
+    } catch (e: any) {
+      if (!abortRef.current) {
+        updateStatus('error', { error: e.message })
+      }
+    }
+
+    doneCountRef.current++
+    setProgress({ done: doneCountRef.current, total: inputFiles.size })
+  }, [inputFiles, outputHandle])
+
   const handleConvert = useCallback(async () => {
     if (!outputHandle || inputFiles.size === 0 || !wasmReady) return
 
     abortRef.current = false
+    doneCountRef.current = 0
     setConverting(true)
     setProgress({ done: 0, total: inputFiles.size })
 
     const entries = Array.from(inputFiles.values())
 
-    for (let i = 0; i < entries.length; i++) {
-      if (abortRef.current) break
+    let nextIdx = 0
+    const workers: Promise<void>[] = []
 
-      const entry = entries[i]
+    const makeWorker = async () => {
+      while (true) {
+        const i = nextIdx++
+        if (i >= entries.length || abortRef.current) break
 
-      const setStatus = (status: FileItem['status'], extra?: Partial<FileItem>) =>
-        setFileItems((prev) => prev.map((item, idx) =>
-          idx === i ? { ...item, status, ...extra } : item
-        ))
+        const setStatus = (status: FileItem['status'], extra?: Partial<FileItem>) =>
+          setFileItems((prev) => prev.map((item, idx) =>
+            idx === i ? { ...item, status, ...extra } : item
+          ))
 
-      setStatus('converting')
-
-      try {
-        const buf = await entry.file.arrayBuffer()
-        const result = await convertNcm(buf)
-        let audio = result.data
-
-        // Fetch cover image if available
-        let coverData: Uint8Array | undefined
-        if (result.coverUrl) {
-          setStatus('fetching_cover')
-          try {
-            const resp = await fetch(result.coverUrl)
-            if (resp.ok) {
-              const coverBuf = await resp.arrayBuffer()
-              coverData = new Uint8Array(coverBuf)
-            }
-          } catch {
-            // cover fetch failed, proceed without it
-          }
-        }
-
-        // Embed metadata + cover
-        if (result.title || result.artist || result.album || coverData) {
-          setStatus('writing')
-          audio = await embedMetadata(
-            audio,
-            result.format,
-            { title: result.title, artist: result.artist, album: result.album },
-            coverData
-          )
-        } else {
-          setStatus('writing')
-        }
-
-        const base = entry.name.replace(/\.ncm$/i, '')
-        const outName = `${base}.${result.format}`
-
-        const fileHandle = await outputHandle.getFileHandle(outName, { create: true })
-        const writable = await fileHandle.createWritable()
-        await writable.write(audio)
-        await writable.close()
-
-        setStatus('done', { format: result.format })
-      } catch (e: any) {
-        setStatus('error', { error: e.message })
+        await processOne(entries[i], i, setStatus)
       }
-
-      setProgress({ done: i + 1, total: entries.length })
     }
 
+    const n = Math.min(concurrency, entries.length)
+    for (let w = 0; w < n; w++) {
+      workers.push(makeWorker())
+    }
+
+    await Promise.all(workers)
     setConverting(false)
-  }, [inputFiles, outputHandle, wasmReady])
+  }, [inputFiles, outputHandle, wasmReady, processOne, concurrency])
 
   const handleAbort = useCallback(() => {
     abortRef.current = true
@@ -168,6 +189,20 @@ export default function App() {
             {inputFiles.size > 0 && (
               <div className="mt-3 animate-fade-in flex items-center gap-3">
                 <StatusBar progress={progress} />
+                <div className="flex shrink-0 items-center gap-2 text-xs text-slate-400">
+                  <span>并行</span>
+                  <select
+                    value={concurrency}
+                    onChange={(e) => setConcurrency(Number(e.target.value))}
+                    disabled={converting}
+                    className="rounded-lg bg-slate-800 border border-slate-700 px-2 py-2 text-slate-200
+                               focus:outline-none focus:border-indigo-500 disabled:opacity-40"
+                  >
+                    {[1, 2, 3, 4, 6, 8, 12, 16, 24, 32].map((n) => (
+                      <option key={n} value={n}>{n}</option>
+                    ))}
+                  </select>
+                </div>
                 <button
                   onClick={handleConvert}
                   disabled={!canConvert}