Three fixes from Opus advisor review of stage-261:
1. CRITICAL: dropdown-survives-resize bug. The composerToolsetsDropdown is a
DOM sibling of composerToolsetsWrap, not a child, so CSS hiding the wrap
does not cascade-hide an open dropdown. If a user opens the dropdown at
composer-footer >= 1100px and then opens the workspace panel (or resizes
the window), the dropdown would stay open without a visible anchor.
Fixed in three places (defense-in-depth):
- resize listener: closes dropdown when chip.offsetParent === null
- _positionToolsetsDropdown: closes if chip hidden (defense-in-depth)
- toggleToolsetsDropdown: early-returns if chip hidden (defense against
future #1431 redesign code that might invoke from elsewhere)
2. MEDIUM: display:flex changed to display:block to match sibling wraps
(.composer-profile-wrap, .composer-model-wrap, .composer-reasoning-wrap
all use the natural block display).
3. Added 3 new regression tests to pin all three guards.
Refs #1431, #1433.
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