feat: Puente Mayúscula-Minúscula + TTS SpeechSynthesis + E2E fixes

app/api/tts/route.ts

@@ -0,0 +1,49 @@
+import { NextRequest, NextResponse } from "next/server"
+import { execSync } from "child_process"
+import { existsSync, mkdirSync } from "fs"
+import { createHash } from "crypto"
+import { readFile, mkdir } from "fs/promises"
+import { join } from "path"
+
+const CACHE_DIR = join(process.cwd(), "public", "tts-cache")
+
+async function ensureCacheDir() {
+  if (!existsSync(CACHE_DIR)) {
+    await mkdir(CACHE_DIR, { recursive: true })
+  }
+}
+
+function getCachePath(text: string): string {
+  const hash = createHash("md5").update(text).digest("hex")
+  return join(CACHE_DIR, `${hash}.wav`)
+}
+
+export async function GET(request: NextRequest) {
+  const text = request.nextUrl.searchParams.get("text")
+  if (!text || text.length > 200) {
+    return NextResponse.json({ error: "text param required (max 200 chars)" }, { status: 400 })
+  }
+
+  await ensureCacheDir()
+  const cachePath = getCachePath(text)
+
+  if (!existsSync(cachePath)) {
+    try {
+      execSync(
+        `espeak-ng -v es-mx -s 140 -p 60 "${text.replace(/"/g, '\\"')}" -w "${cachePath}"`,
+        { timeout: 10000 },
+      )
+    } catch {
+      return NextResponse.json({ error: "TTS generation failed" }, { status: 500 })
+    }
+  }
+
+  const audioBuffer = await readFile(cachePath)
+  return new NextResponse(audioBuffer, {
+    headers: {
+      "Content-Type": "audio/wav",
+      "Content-Length": audioBuffer.length.toString(),
+      "Cache-Control": "public, max-age=31536000, immutable",
+    },
+  })
+}