fix: delete-area hit testing at non-default zoom (#10095)

[mikeharv]

The basics

• I validated my changes

The details

Resolves

Fixes #10095

Proposed Changes

Hit-test delete areas now us client/viewport coordinates (clientX/clientY) instead of a client-to-workspace-to-client round-trip

Reason for Changes

After #10078, delete styling would still appear at non-default zoom but blocks were not reliably deleted and the trashcan lid did not animate. The coordinate round-trip misaligned hit tests with getBoundingClientRect() at certain zoom levels, but using client coordinates fixes that.

Test Coverage

• Extended dragger_test.js with generated trashcan/toolbox delete tests at zoom 0.7 and 1.5 (delete style, trashcan lid, disposal)
• Generated extra mutator workspace tests with a zoomed parent workspace (delete on pointer-over-area; no false positive on origin-only overlap). Unrelated to bug report, but felt useful enough to add.

[mikeharv]

CI on this PR is failing because main has a package.json / package-lock.json override mismatch (npm ci missing eslint@10.3.0 / prettier@3.8.3). That is unrelated to the delete-area fix.

I opened a separate chore PR to fix main for everyone: #10097

I rebased zoom-delete onto that fix so Node.js CI should pass here once the re-run completes.

[lizschwab]

Looks good once we get CI happy again