Replace the curl-based Taskfile download task with a Go binary that
concurrently fetches datastar.js, datastar.js.map, daisyui.mjs, and
daisyui-theme.mjs. Update vendored libs to latest versions.
Use gotailwind (standalone Tailwind v4 via Go tool) with DaisyUI
plugin files — no npm needed. CSS is compiled at build time and
embedded via a Via Plugin that serves it as a static file.
Custom "connect4" theme: light, warm, playful palette with red/yellow
accents matching game pieces and board blue accent.
