drop python backend layer

frontend/vite.config.ts

@@ -1,12 +1,58 @@
-import { defineConfig } from 'vite'
+import { createReadStream, existsSync, statSync } from 'node:fs'
+import { join, resolve } from 'node:path'
+import { fileURLToPath } from 'node:url'
+import type { IncomingMessage, ServerResponse } from 'node:http'
+import { defineConfig, type Connect, type Plugin } from 'vite'
 import { svelte } from '@sveltejs/vite-plugin-svelte'
 
+const repoRoot = resolve(fileURLToPath(import.meta.url), '../..')
+const assetsDir = resolve(repoRoot, 'assets')
+
+function serveStatic(root: string): Connect.NextHandleFunction {
+  return (req, res, next) => {
+    const url = (req.url ?? '/').split('?')[0]
+    const filePath = resolve(join(root, url))
+    if (!filePath.startsWith(root) || !existsSync(filePath)) {
+      next()
+      return
+    }
+    const stat = statSync(filePath)
+    if (!stat.isFile()) {
+      next()
+      return
+    }
+    serveFile(filePath, res)
+  }
+}
+
+function serveFile(filePath: string, res: ServerResponse<IncomingMessage>): void {
+  const ext = filePath.split('.').pop()?.toLowerCase()
+  const types: Record<string, string> = {
+    json: 'application/json',
+    mp3: 'audio/mpeg',
+  }
+  res.setHeader('Content-Type', types[ext ?? ''] ?? 'application/octet-stream')
+  createReadStream(filePath).pipe(res)
+}
+
+/** Serve repo-level assets/ at /assets in dev and preview. */
+function serveRepoAssets(): Plugin {
+  return {
+    name: 'serve-repo-assets',
+    configureServer(server) {
+      server.middlewares.use('/assets', serveStatic(assetsDir))
+    },
+    configurePreviewServer(server) {
+      server.middlewares.use('/assets', serveStatic(assetsDir))
+    },
+  }
+}
+
 export default defineConfig({
-  plugins: [svelte()],
+  plugins: [svelte(), serveRepoAssets()],
   server: {
-    proxy: {
-      '/api': 'http://127.0.0.1:8000',
-      '/assets': 'http://127.0.0.1:8000',
+    fs: {
+      allow: [repoRoot],
     },
   },
 })