Enable dataframe streaming across Python FFI

[teh-cmc]

Title.

Just trying not to bury the actual important thing into the previous mammoth PR 🫠

• DNM: requires Implement safe storage handles #7934

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
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[teh-cmc]

@rerun-bot full-check

[github-actions]

Started a full build: https://github.com/rerun-io/rerun/actions/runs/11579787308

[emilk]

If the PR only removes code, but the code it removes are /* */ pairs… is it removing code, or adding it? 🧘

[teh-cmc]

If a forest falls but also a tree does it sound, yes?