[yusukebe]

Move the toolchain to Vite+, like honojs/hono: vp fmt and vp lint replace Prettier and ESLint, vp test runs Vitest 5, and vp pack replaces tsdown. The config is in vite.config.ts, with the same format options and lint rules as hono. CI runs pnpm run check.

• vite points to @voidzero-dev/vite-plus-core, as vp migrate sets it. The tests of --runtime vite use it.
• src changes are only the import order from oxfmt, plus build.test.ts: Vitest 5 no longer mocks a data: URL import, so the test imports the bundle for real.
• The built dist/cli.js has the same imports as before.

The author should do the following, if applicable

• Add tests
• Run tests
• pnpm run check:fix to format and lint the code
• Add TSDoc/JSDoc to document the code