fix: Don't select shadow blocks on click

[gonfunko]

The basics

• I validated my changes

The details

Resolves

Fixes #9180

Proposed Changes

This PR fixes a bug that could cause shadow blocks to temporarily or permanently become selected when clicked on. Clicking on a block triggers a block start gesture, which correctly handles shadow blocks when determining what to select (their parent block). Click events bubble up to the workspace and trigger a workspace start gesture as well though, and that was focusing the start block, which is sometimes different than the target block that the block gesture start handler resolves. I updated the check for "nothing else should be focused" to check targetBlock rather than startBlock, and removed the explicit call focus the target/start block, since that would have already happened in the block start gesture handler.

I verified that shadow blocks still become selected via keyboard navigation, that clicking a shadow block focuses its parent block, that workspace comments and bubbles are still selectable, and that clicking the workspace focuses the workspace.

[rachel-fenichel]

I verified that shadow blocks still become selected via keyboard navigation, that clicking a shadow block focuses its parent block, that workspace comments and bubbles are still selectable, and that clicking the workspace focuses the workspace.

Please add automated tests for these cases.

[BenHenning]

Nice find. Is it possible to test the specific scenarios that were breaking?

Edit: Asked this 8 minutes after Rachel did. :)

[gonfunko]

Added a test to verify that clicked shadow blocks don't become selected. Ready for another look @BenHenning

[BenHenning]

Thanks for adding the new test, this LGTM!