Use native node for running the bot

[JstnMcBrd]

Follow up to #541

Modernizes and simplifies our setup

Changes

• Fixed the required node version
  • Type-stripping is not unflagged in all version of Node 23, so it should be excluded
• Rewrote all imports from .js to .ts
• Enforced erasableSyntaxOnly
  • This means not using enums - only downside
• Pointed node directly to src/main.ts
• Removed the build step
• Replaced it with a type-checking script
• Removed all references to dist
• Updated the Dockerfile to reflect build changes
• Excluded test files from type-checking and typed linting
  • There's always been a ton of unaddressed type errors in our test files, but the build step never caught them because it excluded test files
  • The type-checking step doesn't exclude test files, so all the type errors are visible now
  • There's way too many to fix right now, so I'm saving it for later

[JstnMcBrd]

The branch protection rules need to be updated to expect CI / Type check instead of CI / Build.

[AverageHelper]

If we go this route, we can probably do away with source-map-support too, since we no longer have a "build" stage to generate those.

[AverageHelper]

Not sure about removing this line. Shouldn't we update the package lists before trying to install packages?

[AverageHelper]

I'm not sure on removing the "build" stage yet. I'm hoping to eventually set up something like Rollup so we can tree-shake and avoid including node_modules in the final bundle, and setting that up would require reinstating that build step and possibly undoing this entire PR later 😓