feat(drawer): Add a drawer component

[oneslash]

Closes: #98

Summary

• Ports a shadcn-style “modal sheet” Drawer to Basecoat with 4-side support (data-side) and drag-to-snap/close behavior.

How To Test

• npm i && npm run docs:dev
• Visit /components/drawer and verify: open/close (click + Esc + overlay), focus return, each side, drag handle snaps/closes, snap-points example, opening a second drawer closes the first.

[hunvreus]

Nice. I think I may want to modify some of the styles. Did you get most of these styles out of https://github.com/shadcn-ui/ui/blob/main/apps/v4/registry/new-york-v4/ui/drawer.tsx ?

I'll get to this in the next week or so as I need it for devpu.sh.

[oneslash]

@hunvreus, yes, I ported styles from the new-york-v4/ui/drawer.tsx :) I miss this component for my https://github.com/open-sspm/open-sspm 😄

I think I may want to modify some of the styles

Sure, that will be awesome!