Remove unused plotly and kaleido dependencies

[bencehezso]

Summary

Removes the plotly and kaleido packages, which are no longer used.

These were part of an old charting stack (Plotly for figures, kaleido as its
image-export backend). Chart and image generation now runs entirely on
ReportLab's native graphics primitives (Drawing, Pie, Polygon, Wedge,
etc. in core/utils_report_pdf.py and core/utils_report_egress.py). No Plotly
usage remains anywhere in the codebase — only leftover log-silencing lines — so
both packages are dead weight. kaleido also ships a bundled Chromium binary, so
dropping it meaningfully slims the install.

Changes

• Remove plotly==6.7.0 and kaleido==1.3.0 from requirements.txt
• Remove plotly==6.7.0 and kaleido==1.3.0 from pyproject.toml
• Remove the leftover kaleido and choreographer logging lines in main.py