Move application of content mask and z-index into Interactivity::paint

This allows the content mask to correctly apply to bounds used in event handlers,
which prevents content under opaque borders from being hovered in overflow hidden
containers.

Co-Authored-By: Antonio <antonio@zed.dev>
Co-Authored-By: Max Brunsfeld <max@zed.dev>

crates/workspace2/src/dock.rs

@@ -537,6 +537,7 @@ impl Render for Dock {
             div()
                 .flex()
                 .border_color(cx.theme().colors().border)
+                .overflow_hidden()
                 .map(|this| match self.position().axis() {
                     Axis::Horizontal => this.w(px(size)).h_full().flex_row(),
                     Axis::Vertical => this.h(px(size)).w_full().flex_col(),