feat(ui): component redesign pass and fixes, release ui 0.8.87

Redesign
- Shared field foundation rules (duplicated across 15 form components and
  emitted globally) are now identical everywhere, so later copies no longer
  silently override earlier redesigns.
- Drawn checkbox and radio controls, white switch thumbs (the thumb was the
  text colour, a black blob in light mode), recessed field wells, keycap
  actions in Modal, Drawer, Popover, Toaster, Pagination, Stepper, DataTable.
- Menus (Dropdown, ContextMenu, Popover, Select dropdown, Navbar panels) share
  one flat raised panel with neutral hover rows and mono section labels.
- Alerts with an accent rail and icon chip; card headers without the grey
  band; accordion, collapse, list, list group, timeline, stats, metrics,
  chat, skeleton, avatar group, clipboard, splitter, section, sidebar,
  navbar and upload progress restyled.
- Chart rebuilt: nice y-axis ticks, gridlines, rounded bars, line and area
  modes, hover tooltips, hidden series leave the scale.

Fixes
- Checkbox and radio labels toggle their input again (empty for="" broke it).
- TimePicker kept every clicked time pressed; only the chosen hour and
  minute are pressed now, and nothing is pressed before a value exists.
- ColorPicker hex readout now follows the picked colour.
- Disabled FileInput no longer shows the native file-input text.
- Date and time panels float instead of pushing content.
- ContextMenu opened at the pointer closes on scroll.
- Drawer left/top/bottom placements slide from their own edge again.
- Image-only Card no longer renders an empty body strip.
- Timeline supports item.time, current/upcoming states, sizes and
  compact/alternate variants; showcase demos use distinct variants.
- ChatBubble: delivery receipts (sending/sent/delivered/read/failed/error)
  and meta aligned to its bubble.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

packages/ui/components/LayoutSplitter.wrn

@@ -125,11 +125,16 @@ component LayoutSplitter {
     .wrn-splitter {
       --splitter-accent: var(--wrn-color-primary);
       display: grid;
-      /* The first track follows the size the runtime resolves. */
       grid-template-columns: var(--wrn-split, 50%) auto minmax(0, 1fr);
       align-items: stretch;
       width: 100%;
       min-width: 0;
+      min-height: 14rem;
+      overflow: hidden;
+      border: 1px solid var(--wrn-color-border);
+      border-radius: var(--wrn-radius);
+      background: var(--wrn-color-surface);
+      box-shadow: var(--wrn-shadow-1);
     }
 
     .wrn-splitter[data-color="secondary"] {
@@ -157,45 +162,57 @@ component LayoutSplitter {
       min-width: 0;
       min-height: 0;
       overflow: auto;
+      padding: 1rem 1.125rem;
+      color: var(--wrn-color-text);
+      font-size: 0.875rem;
+      line-height: 1.55;
     }
 
     .wrn-splitter__handle {
+      position: relative;
       display: flex;
       align-items: center;
       justify-content: center;
       flex: 0 0 auto;
-      padding: 0 0.25rem;
+      width: 0.75rem;
+      padding: 0;
       border: 0;
-      background: transparent;
+      background: var(--wrn-color-surface);
       cursor: col-resize;
-      /* Without this the pointer drag selects the text in both panes. */
       touch-action: none;
       user-select: none;
     }
 
     .wrn-splitter[data-orientation="vertical"] .wrn-splitter__handle {
-      padding: 0.25rem 0;
+      width: auto;
+      height: 0.75rem;
+      padding: 0;
       cursor: row-resize;
     }
 
     .wrn-splitter__grip {
+      position: relative;
+      z-index: 1;
       display: block;
-      width: 2px;
-      height: 100%;
-      min-height: 1.5rem;
+      width: 0.375rem;
+      height: 1.75rem;
+      min-height: 0;
+      border: 1px solid var(--wrn-color-border-strong, var(--wrn-color-border));
       border-radius: 999px;
-      background: var(--wrn-color-border);
-      transition: background 140ms ease;
+      background: var(--wrn-color-surface-raised, var(--wrn-color-surface));
+      box-shadow: var(--wrn-shadow-1);
+      transition: background 140ms ease, border-color 140ms ease, transform 140ms ease;
     }
 
     .wrn-splitter[data-orientation="vertical"] .wrn-splitter__grip {
-      width: 100%;
-      min-width: 1.5rem;
-      height: 2px;
+      width: 1.75rem;
+      min-width: 0;
+      height: 0.375rem;
     }
 
     .wrn-splitter__handle:hover .wrn-splitter__grip,
     .wrn-splitter[data-wrn-splitter-dragging="true"] .wrn-splitter__grip {
+      border-color: var(--splitter-accent);
       background: var(--splitter-accent);
     }
 
@@ -218,8 +235,43 @@ component LayoutSplitter {
       }
 
       .wrn-splitter__handle {
+        width: auto;
+        height: 1px;
         cursor: default;
+        background: var(--wrn-color-border);
       }
+
+      .wrn-splitter__handle::before,
+      .wrn-splitter__grip {
+        display: none;
+      }
+    }
+  
+    .wrn-splitter__handle::before {
+      position: absolute;
+      inset-block: 0;
+      inset-inline-start: calc(50% - 0.5px);
+      width: 1px;
+      background: var(--wrn-color-border);
+      content: "";
+      transition: background 140ms ease;
+    }
+  
+    .wrn-splitter[data-orientation="vertical"] .wrn-splitter__handle::before {
+      inset-block: auto;
+      inset-inline: 0;
+      top: calc(50% - 0.5px);
+      width: auto;
+      height: 1px;
+    }
+  
+    .wrn-splitter__handle:hover::before,
+.wrn-splitter[data-wrn-splitter-dragging="true"] .wrn-splitter__handle::before {
+      background: color-mix(in srgb, var(--splitter-accent) 60%, var(--wrn-color-border));
+    }
+  
+    .wrn-splitter__pane--end {
+      background: var(--wrn-color-surface-soft, var(--wrn-color-surface));
     }
   }
 }