feat: initial Transmute app — universal client-side file converter

Full-stack client-side file converter with Next.js 15 static export.
Supports images (Canvas API), documents (mammoth/pdf-lib/jspdf),
audio/video (ffmpeg.wasm), and data formats (papaparse/yaml/xml).
Dark industrial UI with Space Grotesk + JetBrains Mono, animated
drop zone, glassmorphism file cards, progress rings, and ZIP downloads.
Zero server dependencies — files never leave the browser.

public/vercel.svg

@@ -0,0 +1 @@
+<svg fill="none" xmlns="http://www.w3.org/2000/svg" viewBox="0 0 1155 1000"><path d="m577.3 0 577.4 1000H0z" fill="#fff"/></svg>