wip(drawer): port JS implementation to pure Rust/Leptos

[max-wells]

Summary

The current Drawer component (app_crates/registry/src/ui/drawer.rs) delegates all behavior to the JavaScript implementation in public/app_components/vaul_drawer.js. A full Rust/Leptos port exists in app/src/domain/tests/drawer_tofix.rs but was reverted because it didn't match the JS behavior correctly.

Goal

Make drawer_tofix.rs behavior-identical to the JS implementation, then promote it to replace drawer.rs (eliminating the JS dependency).

What needs fixing

• Verify open/close animation sequencing matches JS (data-state, hidden, transform transitions)
• Verify drag-to-close behavior (velocity threshold, close threshold, damping on reverse drag)
• Verify overlay opacity animation during drag
• Verify body scroll lock / unlock
• Verify focus trap (Tab/Shift+Tab cycling, focus restore on close)
• Verify wrapper scale animation ([data-vaul-drawer-wrapper])
• Verify all positions: Bottom, Left, Right
• Verify both variants: Inset, Floating

Test demos needed

Add demos in app/src/domain/tests/ that exercise the Rust impl in isolation:

• Basic open/close (bottom)
• Side drawers (left, right) — both inset and floating
• Non-dismissible drawer
• Nested drawer
• Scrollable content (drag prevention while scrolled)
• Focus trap

Files

• Rust port: app/src/domain/tests/drawer_tofix.rs
• Current JS-backed impl: app_crates/registry/src/ui/drawer.rs
• Existing demos (using JS impl): app_crates/registry/src/demos/demo_drawer*.rs
• Test page: app/src/domain/tests/page_test.rs

[max-wells]

A pure Rust/Leptos port is already well underway in app/src/domain/tests/drawer_tofix.rs. The core logic is implemented:

• Drag-to-close with velocity/threshold detection and damping on reverse drag
• Overlay opacity animation during drag
• Wrapper scale animation ([data-vaul-drawer-wrapper])
• Body scroll lock / unlock
• Focus trap (Tab/Shift+Tab, Escape, focus restore on close)
• All three positions: Bottom, Left, Right
• Both variants: Inset, Floating
• Open/close animation sequencing with epoch guards to prevent race conditions

The port is not yet promoted to replace drawer.rs because the animation sequencing and some edge cases don't fully match the JS behavior. Work is ongoing — this is tracked and in progress.