leifstout/dataServiceTyped ? reverse-engineered prompt

Build me a Roblox Luau data service for player data that is persistent, automatically replicated, and easy to observe from the game code.

I want a clean typed API so I can define player data, load it when a player joins, save it safely, and react when values change without writing a bunch of boilerplate. It should feel simple to use in a normal Roblox project, with good type safety and clear documentation comments. Make sure it works well for common player data like coins, level, inventory, and settings, and that changes on the server can be observed by other parts of the game.

Please set it up as a reusable package, with examples or a small demo of how to initialize it and use it in a game. If you need to check current Roblox or Luau docs while building it, go ahead and look them up online.