Add buttons, menus and the rest of M3 Expressive's actions

<x-button> (label buttons, icon buttons and toggles in five sizes, with
filled, tonal, outlined, elevated and text variants in any colour role),
<x-tooltip>, <x-menu> with items, groups and separators, <x-button-group>,
<x-group> as a connected button group, <x-split-button>, <x-fab>,
<x-fab-menu> and <x-loading>. Sizes, colours and shapes come from
androidx Compose Material 3's tokens; the loading indicator ports its
Morph into SVG + SMIL.

Menus follow WAI-ARIA's menu button pattern on popovers placed by CSS
anchor positioning. Browser tests run in Chromium, Firefox and WebKit.
The showcase fetches the icon names on demand: inlined, they tripped
Pest's test server into HTTP 431s under Firefox.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01V9NnLxnPp8vaaurb3Z1MFy

resources/js/tooltip.js

@@ -0,0 +1,57 @@
+/**
+ * `materialTooltip`: shows an `<x-tooltip>` popover for the control it belongs to.
+ *
+ * The trigger is the popover's parent element (the button, or the standalone wrapper). Hover
+ * counts only for a pointer that can hover, after a short delay so a pointer passing over a
+ * toolbar does not flash every label; keyboard focus shows it at once. A press, leaving, blur
+ * and Escape hide it.
+ */
+const HOVER_DELAY_MS = 500
+
+document.addEventListener('alpine:init', () => {
+    window.Alpine.data('materialTooltip', () => ({
+        timer: null,
+        listeners: [],
+
+        init() {
+            const tip = this.$el
+            const trigger = tip.parentElement
+
+            const open = () => tip.matches(':popover-open')
+
+            const show = (delay) => {
+                clearTimeout(this.timer)
+                this.timer = setTimeout(() => {
+                    if (tip.isConnected && !open()) {
+                        tip.showPopover()
+                    }
+                }, delay)
+            }
+
+            const hide = () => {
+                clearTimeout(this.timer)
+
+                if (open()) {
+                    tip.hidePopover()
+                }
+            }
+
+            this.listen(trigger, 'pointerenter', (event) => event.pointerType === 'mouse' && show(HOVER_DELAY_MS))
+            this.listen(trigger, 'pointerleave', hide)
+            this.listen(trigger, 'pointerdown', hide)
+            this.listen(trigger, 'focusin', () => trigger.matches(':focus-within:has(:focus-visible), :focus-visible') && show(0))
+            this.listen(trigger, 'focusout', hide)
+            this.listen(document, 'keydown', (event) => event.key === 'Escape' && hide())
+        },
+
+        listen(target, type, handler) {
+            target.addEventListener(type, handler)
+            this.listeners.push(() => target.removeEventListener(type, handler))
+        },
+
+        destroy() {
+            clearTimeout(this.timer)
+            this.listeners.forEach((remove) => remove())
+        },
+    }))
+})