Make rerun-py use an embedded rerun-cli executable

[jleibs]

What

• Resolves: Split viewer binary out from python_bridge.so #5196

• Move rerun_py over to a dependency on re_sdk instead of rerun

• Modify the pyproject / build script to look for a bin/rerun in the python project.

• Update the launch/spawn scripts to use the embedded copy of the rerun executable.

• Spawn now dispatches through the SDK the same way as cpp / rust.

• When executed inside the editable dev environment, use the copy of rerun from target/debug

• Build and upload a copy of rerun-cli to embed into the wheel during PR builds.

• Verify wheels build correctly on nightly

Checklist

• I have read and agree to Contributor Guide and the Code of Conduct
• I've included a screenshot or gif (if applicable)
• I have tested the web demo (if applicable):
  • Using examples from latest main build: rerun.io/viewer
  • Using full set of examples from nightly build: rerun.io/viewer
• The PR title and labels are set such as to maximize their usefulness for the next release's CHANGELOG
• If applicable, add a new check to the release checklist!

• PR Build Summary
• Recent benchmark results
• Wasm size tracking

To run all checks from main, comment on the PR with @rerun-bot full-check.

[github-actions]

Deployed docs

Commit	Link
4a95061	https://landing-qavaj5zv2-rerun.vercel.app/docs

[emilk]

Very nice!