Rewrite the divider without Tailwind

Plan step 36 (containment group): <x-divider> moves its class lists
into resources/css/components/divider.css, keyed on data-md-divider,
data-md-orientation, data-md-inset/middle and data-md-divider-heading/
-text for the subheader form (DividerTokens.kt; docs/reference/m3
§ Divider). Imported from the Containment block of components.css.

Hooks renamed: none of divider's own (it had no data-* hooks before),
but its rendered attribute order moved data-md-* ahead of role/aria-*,
which ToolbarTest.php's regex for a toolbar's vertical divider depended
on; fixed in the same commit. form.css picks up the @import './divider.css'
its TODO(step 36) marker was waiting on, since form.blade.php renders
<x-divider> and divider.css now carries the material.components layer.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Qwx5USif3wFFmxtHg5U1g9

resources/css/components.css

@@ -56,5 +56,6 @@
 @import './components/timepicker.css';
 
 /* Containment */
+@import './components/divider.css';
 
 /* Navigation */

resources/css/components/divider.css

@@ -0,0 +1,75 @@
+/*
+ * <x-divider>: M3's divider (DividerTokens.kt, androidx Compose Material 3, Apache-2.0) — a single
+ * 1px outline-variant line, full-width by default, `data-md-inset` 16px from the start or
+ * `data-md-middle` 16px from both ends (docs/reference/m3/components-actions-communication-containment.md
+ * § Divider → Specs: "Divider inset left margin 16dp", "Divider middle-inset left/right margin
+ * 16dp"). A vertical divider (`data-md-orientation="vertical"`) stretches the height of its row
+ * instead of drawing a width.
+ *
+ * `data-md-divider-heading` draws the divider with a subheader, M3's way to head a group in a list
+ * or a menu: the words lead, 4px of gap to the rule that runs on from them, 8px short of the end
+ * and 8px above the next row (the same section's "Space between divider & supporting text 4dp",
+ * "Divider right margin 8dp", "Divider bottom margin 8dp"). The label, `data-md-divider-text`, is
+ * the rich tooltip's subhead type — title-small in on-surface-variant — since the divider's own
+ * page names no type role for it.
+ */
+
+@layer material.reset, material.tokens, material.base, material.layout, material.components, material.text, material.visibility;
+
+@layer material.components {
+    [data-md-divider] {
+        flex-shrink: 0;
+        background-color: var(--md-sys-color-outline-variant);
+    }
+
+    [data-md-divider][data-md-orientation='horizontal'] {
+        width: auto;
+        height: 1px;
+    }
+
+    [data-md-divider][data-md-orientation='vertical'] {
+        width: 1px;
+        align-self: stretch;
+    }
+
+    [data-md-divider][data-md-orientation='horizontal'][data-md-inset] {
+        margin-inline-start: var(--md-sys-measurement-space200);
+    }
+
+    [data-md-divider][data-md-orientation='horizontal'][data-md-middle] {
+        margin-inline: var(--md-sys-measurement-space200);
+    }
+
+    [data-md-divider][data-md-orientation='vertical'][data-md-middle] {
+        margin-block: var(--md-sys-measurement-space100);
+    }
+
+    [data-md-divider-heading] {
+        display: flex;
+        flex-shrink: 0;
+        align-items: center;
+        gap: var(--md-sys-measurement-space50);
+        padding-bottom: var(--md-sys-measurement-space100);
+    }
+
+    [data-md-divider-heading][data-md-inset] {
+        margin-inline-start: var(--md-sys-measurement-space200);
+    }
+
+    [data-md-divider-heading][data-md-middle] {
+        margin-inline: var(--md-sys-measurement-space200);
+    }
+
+    [data-md-divider-text] {
+        flex-shrink: 0;
+        color: var(--md-sys-color-on-surface-variant);
+        font: var(--md-sys-typescale-title-sm);
+        letter-spacing: var(--md-sys-typescale-title-sm-tracking);
+    }
+
+    [data-md-divider-heading] [data-md-divider] {
+        flex: 1 1 0%;
+        min-width: 0;
+        margin-inline-end: var(--md-sys-measurement-space100);
+    }
+}

resources/css/components/form.css

@@ -17,7 +17,7 @@
 
 @layer material.reset, material.tokens, material.base, material.layout, material.components, material.text, material.visibility;
 
-/* TODO(step 36): @import './divider.css' once <x-divider> leaves Tailwind (containment stream). */
+@import './divider.css';
 
 @layer material.components {
     [data-md-form] {