Fix Missing @ffmpeg/ffmpeg Wasm in OpenCut

If the editor logs Failed to load ffmpeg-core.wasm, the bundle cannot find the WASM core.

Checklist

1. Install the package:

   bun add @ffmpeg/ffmpeg @ffmpeg/core
2. Configure static file serving in next.config.mjs:

   const withTM = require('next-transpile-modules')(['@ffmpeg/ffmpeg', '@ffmpeg/core']);
   module.exports = withTM({
     webpack: (config) => {
       config.experiments = { ...config.experiments, asyncWebAssembly: true };
       return config;
     }
   });
3. Reference the core explicitly:

   const ffmpeg = createFFmpeg({
     log: true,
     corePath: '/static/ffmpeg/ffmpeg-core.js'
   });
4. Copy assets during build (e.g., using next.config.mjs rewrites or a build script).

Diagram

  flowchart LR
    A[createFFmpeg] --> B[ffmpeg-core.js]
    B --> C[ffmpeg-core.wasm]
    C --> D[Browser]

Host the WASM on a CDN like jsDelivr if you deploy to serverless targets that cannot serve large static files from the filesystem.