## Problem
We have multiple `Collapsible` components.
## Solution
Reduce their number by using only the one from shadcn.
I haven't noticed any visual nor functional changes.
<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->
## Summary by CodeRabbit
* **Refactor**
* Migrated expandable/collapsible UI to a unified shadcn-based
implementation for more consistent expand/collapse behavior across the
app.
* **Style**
* Updated listbox check icon sizing and removed obsolete collapsible
open/close animations.
* **Chores**
* Removed deprecated collapsible variants and consolidated UI component
surface for simpler maintenance.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->
strictNullChecks was off for docs, which lets errors slip through and
leads to incorrect required/optional typing on Zod-inferred types. This
PR enables strictNullChecks and fixes all the existing violations.
* Add lucide-react to docs (to make the autocomplete work).
* Migrate the docs app icons.
* Migrate the ui-patterns.
* Remove the old icons from ui package.
* Migrate the www app from react-feather icons.
* Migrate all of studio icons.
* Migrate the only component in design-system.
* Fix an old import in ui package. Revert an import in docs app.
* Fix some pages in www.
* Remove unneeded files used in generation of icons.
* Fix a prettier error.
* Fix more issues in www.
* Fix an issue in Log Date picker.
* Replace all string sizes with number sizes because the icons grew in some cases.
* Fix more imports in security page.
* Fix an extra import.
* Remove the size prop from all icons if they're in a button and they match the button size.
* Minor fixes for docs and www.
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Co-authored-by: Joshen Lim <joshenlimek@gmail.com>
Gildas Garcia