Defer automargin during scroll-wheel zoom

[keilogic]

Summary

• defer cartesian axis automargin while scroll-wheel zoom is still debouncing
• reuse the existing _replotting guard that pan drag already uses, then let dragTail() release it before the final relayout
• add a Jasmine regression that verifies Plots.doAutoMargin is not called during the wheel event and is called after the debounced relayout

Why

In #6235, scroll zoom can jitter when tick-label width changes and automargin resizes the plot while the wheel interaction is still in progress. Deferring automargin until the final debounced relayout keeps the plot box stable during the scroll interaction.

Fixes #6235.

Validation

• npx @biomejs/biome lint src/plots/cartesian/dragbox.js test/jasmine/tests/cartesian_interact_test.js
• npm run test-jasmine -- cartesian_interact --nowatch --report-spec
  • The new should defer automargin while zooming via mouse wheel regression passed.
  • This Windows/Chrome 148 run still reports one unrelated existing tolerance failure in should compute correct multicategory tick label span during drag (436.3244 vs expected 430 ± 5.5).

Bounty note

If the $100 PayPal/Venmo offer in #6235 still applies after this is accepted/merged, PayPal is available at https://www.paypal.com/paypalme/aogkft.