fix(vite-plugin): include source files for development export

[michaelapollopimentel-svg]

Summary

@rozenite/vite-plugin exposes a development condition that points at ./src/index.ts, but the package files list only publishes dist and templates. That means consumers or tooling that resolve the development condition from the published package can select a file that is not present in the npm tarball.

This adds src to the published files so the advertised development export resolves.

Validation

• git diff --check
• Parsed packages/vite-plugin/package.json as JSON
• Verified exports["."].development points to an existing file covered by the package files list
• Confirmed the current published @rozenite/vite-plugin@1.12.0 tarball does not include src/index.ts

I could not run the full pnpm build/test suite in this environment because pnpm/corepack are not installed.