shinyphaser 0.1.0

Initial CRAN release.

• Added an R6-based PhaserGame API to define Phaser.js scenes, sprites, image assets, groups, and rectangle helpers from R.
• Added Shiny/htmltools bindings that render Phaser games in Shiny apps and synchronize game actions from R to JavaScript.
• Added a sample Shiny app, an end-to-end hedgehog example, package documentation, and test coverage for core methods and sprite behavior.