fix: emoji picker dropdown escapes dialog overflow clipping

Portal the dropdown into the nearest <dialog> element so it stays in
the browser's top layer, and temporarily set overflow:visible on the
dialog while the picker is open so it isn't clipped.

web/src/lib/components/common/EmojiPickerButton.svelte

@@ -10,13 +10,62 @@
 	let { value = $bindable(), placeholder = '⚡', size = 'sm' }: Props = $props();
 
 	let open = $state(false);
+	let triggerEl = $state<HTMLButtonElement>();
+	let dropdownX = $state(0);
+	let dropdownY = $state(0);
+
+	/**
+	 * Portal into the nearest <dialog> (stays in top-layer, escapes overflow
+	 * children like .dialog-body), or document.body if not inside a dialog.
+	 */
+	function portal(node: HTMLElement) {
+		const dialog = triggerEl?.closest('dialog');
+		const target = dialog || document.body;
+		target.appendChild(node);
+
+		// <dialog> has browser-default overflow:auto which clips children.
+		// Temporarily override while the dropdown is mounted.
+		if (dialog) {
+			dialog.style.overflow = 'visible';
+		}
+
+		return {
+			destroy() {
+				node.remove();
+				if (dialog) {
+					dialog.style.overflow = '';
+				}
+			}
+		};
+	}
 
 	function handleWindowClick(e: MouseEvent) {
-		if (open && !(e.target as HTMLElement)?.closest('.emoji-picker-button')) {
-			open = false;
+		if (open) {
+			const target = e.target as HTMLElement;
+			if (!target?.closest('.emoji-picker-button') && !target?.closest('.epb-dropdown')) {
+				open = false;
+			}
 		}
 	}
 
+	function toggleOpen() {
+		if (!open && triggerEl) {
+			const triggerRect = triggerEl.getBoundingClientRect();
+			const dialog = triggerEl.closest('dialog');
+			if (dialog) {
+				// dialog with transform creates a containing block —
+				// position: absolute is relative to it, so offset accordingly
+				const dialogRect = dialog.getBoundingClientRect();
+				dropdownX = triggerRect.left - dialogRect.left;
+				dropdownY = triggerRect.bottom - dialogRect.top + 4;
+			} else {
+				dropdownX = triggerRect.left;
+				dropdownY = triggerRect.bottom + 4;
+			}
+		}
+		open = !open;
+	}
+
 	function handleSelect(emoji: string) {
 		value = emoji;
 		open = false;
@@ -27,17 +76,18 @@
 
 <div class="emoji-picker-button" class:size-md={size === 'md'}>
 	<button
+		bind:this={triggerEl}
 		type="button"
 		class="trigger"
 		class:open
 		class:empty={!value}
-		onclick={() => (open = !open)}
+		onclick={toggleOpen}
 	>
 		{value || placeholder}
 	</button>
 
 	{#if open}
-		<div class="dropdown">
+		<div class="epb-dropdown" use:portal style="position:absolute; z-index:99999; left:{dropdownX}px; top:{dropdownY}px;">
 			<EmojiPicker selected={value} onselect={handleSelect} />
 		</div>
 	{/if}
@@ -80,11 +130,4 @@
 	.trigger.empty {
 		color: var(--text-muted);
 	}
-
-	.dropdown {
-		position: absolute;
-		z-index: 50;
-		top: calc(100% + 4px);
-		left: 0;
-	}
 </style>