This is the first of a few PRs. Deploy to staging will fail until we
have `arcade-core`, `arcade-serve`, and `arcade-ai` released to PyPI.
This PR will release `arcade-core` to PyPI.
### PR Description
* Adds workflow that checks for changes in any pyproject.toml, and if
its version has changed, then tests, builds wheel, then publishes to
PyPI
* Updates the Dockerfile for our new structure
* Updates porter yamls
* Updates `make full-dist`
* Removes a couple unused workflows
Check out https://github.com/ArcadeAI/arcade-ai/actions/runs/15622059209
to see how the new workflow works (note that it failed publishing to
PyPI on purpose)