capsule: keep the drawer hidden when collapsed and pin the capsule width

Two rendering bugs, both from treating set_size_request as a maximum when it
is only a minimum.

The drawer was collapsed with set_size_request(-1, 0) but left visible. GTK
still allocates a visible box its natural height, and this layer-shell surface
has no fixed height, so the window grew to fit the entire results list: the
capsule rendered open at idle with a stray result row beneath it. It is now
hidden while collapsed, revealed in open_fn before the height animation, and
hidden again on the frame the collapse reaches zero so the close stays
animated rather than snapping shut.

The capsule's width came from set_default_width, which is only a preference a
wide child overrides. Combined with the results list propagating its natural
width, the pill stretched well past the theme's 480px. The width request is
now pinned, and the list no longer propagates width.

src/main.rs

@@ -282,6 +282,13 @@ impl SimpleComponent for App {
         // a real value out of it.
         if let Width::Px(px) = window_spec.width {
             root.set_default_width(px);
+            // set_default_width alone is only a preference — a wide child (the
+            // results list, whose natural width is its longest app name plus
+            // icon and wm-class) overrides it, so the capsule rendered far
+            // wider than the theme's 480px and stopped reading as a pill.
+            // Pinning the request keeps the surface at the theme's width
+            // regardless of what the app catalog contains.
+            root.set_size_request(px, -1);
         }
         // "auto" reserves height + top margin so tiled clients sit below the
         // gap — see WindowSpec::exclusive's doc comment (bread-theme).
@@ -979,6 +986,13 @@ impl SimpleComponent for App {
         // same as the demo's `.results { max-height: 0; overflow: hidden }`.
         widgets.drawer_box.set_overflow(gtk4::Overflow::Hidden);
         widgets.drawer_box.set_size_request(-1, 0);
+        // set_size_request is a MINIMUM, not a maximum: GTK still allocates a
+        // visible box its natural height, and this layer-shell surface has no
+        // fixed height, so the window grew to fit the whole results list and
+        // the capsule sat open-at-idle showing a stray row. A hidden widget
+        // requests no size at all, which is what "collapsed" actually needs.
+        // open_fn/close_fn toggle this back on/off around the height animation.
+        widgets.drawer_box.set_visible(false);
 
         // ── Query-mode results (plan §7 phase 6c: `=` calc, `>` cmd, `.`
         // url) ───────────────────────────────────────────────────────────
@@ -1035,6 +1049,10 @@ impl SimpleComponent for App {
             move || {
                 if !launcher_open.get() {
                     launcher_open.set(true);
+                    // Reveal before measuring/animating: while hidden the box
+                    // reports no natural height, so the open animation would
+                    // target 0 and nothing would appear.
+                    drawer_box.set_visible(true);
                     entry.add_css_class("searching");
                     gtk4::prelude::EntryExt::set_alignment(&entry, 0.0);
                     // `.searching` on the root itself (plan §7 phase 6c):
@@ -2429,6 +2447,14 @@ fn animate_drawer_height(
         // valid animation frame, so clamp to 0 rather than -1: a drawer mid-
         // collapse wants zero height, never its natural height.
         target.set_size_request(-1, h.max(0));
+        // Collapse finished: hide the box so it stops claiming natural height.
+        // set_size_request is only a minimum, so a visible-but-zero-request
+        // drawer still gets allocated its children's full height and holds the
+        // capsule open. Hiding here rather than in close_fn keeps the collapse
+        // animated instead of snapping shut on the first frame.
+        if to == 0 && h <= 0 {
+            target.set_visible(false);
+        }
     });
     *anim.borrow_mut() = Some(id);
 }