perf: lazy-load @mdi/js to reduce Vite dev server memory usage

Replace `import * as mdi from '@mdi/js'` (loads ~5MB of SVG paths
synchronously into every HMR update) with a lazy async import that
loads once and caches. MdiIcon and IconPicker now use getMdiPath()
and getAllMdiNames() from the shared mdi-lookup module.

frontend/src/lib/components/IconPicker.svelte

@@ -0,0 +1,93 @@
+<script lang="ts">
+	import { getMdiPath, getAllMdiNames } from '$lib/mdi-lookup';
+
+	let { value = '', onselect } = $props<{
+		value: string;
+		onselect: (icon: string) => void;
+	}>();
+
+	let open = $state(false);
+	let search = $state('');
+	let buttonEl: HTMLButtonElement;
+	let dropdownStyle = $state('');
+
+	const popular = [
+		'mdiServer', 'mdiCamera', 'mdiImage', 'mdiVideo', 'mdiBell', 'mdiSend',
+		'mdiRobot', 'mdiHome', 'mdiStar', 'mdiHeart', 'mdiAccount', 'mdiFolder',
+		'mdiFolderImage', 'mdiAlbum', 'mdiImageMultiple', 'mdiCloudUpload',
+		'mdiEye', 'mdiCog', 'mdiTelegram', 'mdiWebhook', 'mdiMessageText',
+		'mdiCalendar', 'mdiClock', 'mdiMapMarker', 'mdiTag', 'mdiFilter',
+		'mdiSort', 'mdiMagnify', 'mdiPencil', 'mdiDelete', 'mdiPlus',
+		'mdiCheck', 'mdiClose', 'mdiAlert', 'mdiInformation', 'mdiShield',
+		'mdiLink', 'mdiDownload', 'mdiUpload', 'mdiRefresh', 'mdiPlay',
+		'mdiPause', 'mdiStop', 'mdiSkipNext', 'mdiMusic', 'mdiMovie',
+		'mdiFileDocument', 'mdiEmail', 'mdiPhone', 'mdiChat', 'mdiShare',
+	];
+
+	function filtered(): string[] {
+		const allIcons = getAllMdiNames();
+		if (!search) return popular.filter(p => allIcons.includes(p));
+		const q = search.toLowerCase();
+		return allIcons.filter(k => k.toLowerCase().includes(q)).slice(0, 60);
+	}
+
+	function toggleOpen() {
+		if (!open && buttonEl) {
+			const rect = buttonEl.getBoundingClientRect();
+			dropdownStyle = `position:fixed; z-index:9999; top:${rect.bottom + 4}px; left:${rect.left}px;`;
+		}
+		open = !open;
+		if (!open) search = '';
+	}
+
+	function select(iconName: string) {
+		onselect(iconName);
+		open = false;
+		search = '';
+	}
+
+	function handleKeydown(e: KeyboardEvent) {
+		if (e.key === 'Escape' && open) {
+			open = false;
+			search = '';
+		}
+	}
+</script>
+
+<svelte:window onkeydown={open ? handleKeydown : undefined} />
+
+<div class="inline-block">
+	<button type="button" bind:this={buttonEl} onclick={toggleOpen}
+		class="flex items-center justify-center gap-1 px-2 py-2 border border-[var(--color-border)] rounded-md text-sm bg-[var(--color-background)] hover:bg-[var(--color-muted)] transition-colors">
+		{#if value && getMdiPath(value)}
+			<svg viewBox="0 0 24 24" width="18" height="18" fill="currentColor"><path d={getMdiPath(value)} /></svg>
+		{:else}
+			<span class="text-[var(--color-muted-foreground)] text-xs">Icon</span>
+		{/if}
+		<span class="text-xs text-[var(--color-muted-foreground)]">▼</span>
+	</button>
+</div>
+
+{#if open}
+	<div style="position:fixed; top:0; left:0; right:0; bottom:0; z-index:9998;"
+		role="presentation"
+		onclick={() => { open = false; search = ''; }}></div>
+
+	<div style="{dropdownStyle} width: 20rem; background: var(--color-card); border: 1px solid var(--color-border); border-radius: 0.5rem; box-shadow: 0 10px 25px rgba(0,0,0,0.3); padding: 0.75rem;"
+		class="">
+		<input type="text" bind:value={search} placeholder="Search icons..."
+			class="w-full px-2 py-1 mb-2 border border-[var(--color-border)] rounded text-sm bg-[var(--color-background)]" />
+		<div style="display: grid; grid-template-columns: repeat(8, 1fr); gap: 0.25rem; max-height: 14rem; overflow-y: auto; overflow-x: hidden; scrollbar-width: thin;">
+			<button type="button" onclick={() => select('')}
+				class="flex items-center justify-center aspect-square rounded hover:bg-[var(--color-muted)] text-xs text-[var(--color-muted-foreground)]"
+				title="No icon">✕</button>
+			{#each filtered() as iconName}
+				<button type="button" onclick={() => select(iconName)}
+					class="flex items-center justify-center aspect-square rounded hover:bg-[var(--color-muted)] {value === iconName ? 'bg-[var(--color-accent)]' : ''}"
+					title={iconName.replace('mdi', '')}>
+					<svg viewBox="0 0 24 24" width="18" height="18" fill="currentColor"><path d={getMdiPath(iconName)} /></svg>
+				</button>
+			{/each}
+		</div>
+	</div>
+{/if}

frontend/src/lib/components/MdiIcon.svelte

@@ -0,0 +1,9 @@
+<script lang="ts">
+	import { getMdiPath } from '$lib/mdi-lookup';
+
+	let { name = '', size = 18 } = $props<{ name: string; size?: number }>();
+</script>
+
+{#if name && getMdiPath(name)}
+	<svg viewBox="0 0 24 24" width={size} height={size} fill="currentColor"><path d={getMdiPath(name)} /></svg>
+{/if}

frontend/src/lib/mdi-lookup.ts

@@ -0,0 +1,36 @@
+/**
+ * Lazy MDI icon path lookup.
+ *
+ * Instead of `import * as mdi from '@mdi/js'` (which loads ~5MB of SVG paths
+ * into memory), this module loads the full set once on first use and caches it.
+ * Vite only processes the import once, reducing HMR memory pressure.
+ */
+
+let _cache: Record<string, string> | null = null;
+
+async function _load(): Promise<Record<string, string>> {
+	if (_cache) return _cache;
+	const mod = await import('@mdi/js');
+	_cache = mod as unknown as Record<string, string>;
+	return _cache;
+}
+
+// Eagerly load on module init (runs once)
+let _ready: Record<string, string> | null = null;
+_load().then(m => { _ready = m; });
+
+/**
+ * Get SVG path for an icon name. Returns empty string if not found or not yet loaded.
+ */
+export function getMdiPath(name: string): string {
+	if (!name || !_ready) return '';
+	return (_ready as any)[name] || '';
+}
+
+/**
+ * Get all icon names (for IconPicker search). Returns empty array if not yet loaded.
+ */
+export function getAllMdiNames(): string[] {
+	if (!_ready) return [];
+	return Object.keys(_ready).filter(k => k.startsWith('mdi') && k !== 'default');
+}