Fix ejs builds

[zoriya]

Summary

The current ejs build includes code generated from pegjs/peggy (idk why both were still used since peggy is the successor of pegjs, i took the liberty to upgrade uses of pegjs to peggy). This generated code uses commonjs exports, which don't work well in some environments (i'm trying to run it in vite.)

This PR changes the generation mode of peggy to ejs & let babel translate those ejs modules to commonjs for the cjs build.

This PR also removes the Buffer import (which is a node only module, so unavailable on the web). This replaces the use of Buffer with window.atob when unavailable.

Test Plan

I just used my build in my project.

What's required for testing (prerequisites)?

Just use the lib

What are the steps to reproduce (after prerequisites)?

Try to import react-native-svg from a vite based project (one built with one for example).

Compatibility

OS	Implemented
iOS	✅
MacOS	✅
Android	✅
Web	✅

Checklist

• I have tested this on a device and a simulator
• I added documentation in README.md
• I updated the typed files (typescript)
• I added a test for the API in the __tests__ folder

[zoriya]

This file just declares packages needed to work on the project. It's common to upstream this for other users of the nix packet manager. If you don't want it included, I can just remove it. LMK