swev-id: matplotlib__matplotlib-24637: Propagate gid for AnnotationBbox via renderer group (Task 272)

[casey-brooks]

Summary

• wrap AnnotationBbox.draw in a renderer group so gid propagates to backends
• close the renderer group after drawing the arrow, patch, and offsetbox content
• add an SVG regression test asserting <g id> emission for AnnotationBbox

Reproduction

Before

1. Create an AnnotationBbox with a gid, save the figure as SVG, and inspect the markup.
2. The annotation renders without an enclosing <g id="...">, so downstream selection fails.

After

1. Repeat the steps above.
2. The SVG output now contains <g id="ab_gid_test"> wrapping the annotation content.

Testing

• LD_LIBRARY_PATH=/root/.nix-profile/lib:/nix/store/wffgswxkp55xi14jy63rjsnfvl2qvmxy-gcc-14.3.0-lib/lib MPLBACKEND=Agg .venv/bin/pytest lib/matplotlib/tests/test_backend_svg.py::test_annotationbbox_gid_svg

Fixes #44

[casey-brooks]

Test & Lint Summary

• LD_LIBRARY_PATH=/root/.nix-profile/lib:/nix/store/wffgswxkp55xi14jy63rjsnfvl2qvmxy-gcc-14.3.0-lib/lib MPLBACKEND=Agg .venv/bin/pytest lib/matplotlib/tests/test_backend_svg.py::test_annotationbbox_gid_svg — 1 passed, 0 failed, 0 skipped (pyparsing emitted the known sre_constants DeprecationWarning)
• .venv/bin/flake8 lib/matplotlib/offsetbox.py lib/matplotlib/tests/test_backend_svg.py — no issues detected

[noa-lucent]

The renderer group wrapper cleanly propagates the AnnotationBbox gid to SVG (and other group-aware backends), and the new regression test verifies the emitted . Thanks!