feat(ui): migrate entire UI to "Cozy Home" design

Warm, friendly redesign replacing the generic cold-shadcn look. Built as a
swappable token bundle so other presets can be added later; dark mode and the
user-tunable accent hue are retained.

Foundation
- app.css: warm cream (light) + "dusk" (dark) token system; terracotta accent
  (default hue 16); pastel --room-* palette; vivid --status-* (dots/bars) plus
  AA-legible --status-*-ink (text); soft warm shadows; --radius 1rem; font tokens
- Fonts: Fraunces (display) + Figtree (body), self-hosted in static/fonts
  (no Google CDN) so offline/LAN installs work; system-ui fallbacks kept
- h1/h2/h3 render in Fraunces via base layer

Chrome and surfaces
- Sidebar, Header, home, AppCard/BoardCard, BoardHeader, sections, favorites
- 29 widgets + integration renderers: cozy card shells, room-palette charts
- Default background is a static warm "cozy" glow (mesh demoted, rAF gated on
  prefers-reduced-motion)

System-wide
- Status colors tokenized (no raw bg/text-*-500 or status hex); success/warning
  to status tokens, categorical to room palette, errors to destructive
- Inputs rounded-xl; buttons rounded-xl; cards/dialogs rounded-[1.4rem];
  soft-shadow vocabulary only; focus-visible:ring-primary/30
- Forms, admin tables (now cozy cards), dialogs, popovers, auth screens

a11y: reduced-motion guards; darker status "ink" text for AA on cream.
Known tradeoff: terracotta primary + white button text ~2.96:1 (signature color,
user-tunable).

Verified: svelte-check 0/0, build ok, 274 tests pass, eslint 0 errors.
Design refs + system sheet in design-mockups/.

src/lib/components/widget/AppWidget.svelte

@@ -139,14 +139,14 @@
 		href={app.url}
 		target="_blank"
 		rel="noopener noreferrer"
-		class="card-hover group flex items-center gap-2 rounded-lg {cardStyleClass} px-3 py-2 text-left transition-colors hover:border-primary/50"
+		class="card-hover group flex items-center gap-2 rounded-2xl {cardStyleClass} px-3 py-2 text-left transition-colors hover:border-primary/50"
 		data-app-widget
 		data-app-url={app.url}
 		oncontextmenu={handleContextMenu}
 		onclick={recordClick}
 	>
 		<div class="relative flex-shrink-0">
-			<div class="flex h-8 w-8 items-center justify-center rounded-md bg-muted transition-colors group-hover:bg-accent">
+			<div class="flex h-8 w-8 items-center justify-center rounded-xl bg-muted transition-colors group-hover:bg-accent">
 				{#if app.iconType === 'emoji' && app.icon}
 					<span class="text-base">{app.icon}</span>
 				{:else if iconSrc}
@@ -198,7 +198,7 @@
 	<!-- Large: icon + name + description + sparkline + tags + links -->
 	<!-- svelte-ignore a11y_no_static_element_interactions -->
 	<div
-		class="card-hover group rounded-xl {cardStyleClass} p-5 transition-colors hover:border-primary/50"
+		class="card-hover group rounded-[1.4rem] {cardStyleClass} p-5 transition-colors hover:border-primary/50"
 		data-app-widget
 		data-app-url={app.url}
 		oncontextmenu={handleContextMenu}
@@ -211,7 +211,7 @@
 			onclick={recordClick}
 		>
 			<div class="relative">
-				<div class="flex h-16 w-16 items-center justify-center rounded-xl bg-muted transition-colors group-hover:bg-accent">
+				<div class="flex h-16 w-16 items-center justify-center rounded-2xl bg-muted transition-colors group-hover:bg-accent">
 					{#if app.iconType === 'emoji' && app.icon}
 						<span class="text-3xl">{app.icon}</span>
 					{:else if iconSrc}
@@ -294,7 +294,7 @@
 	<!-- Medium (default): icon + name + status + sparkline on hover + links -->
 	<!-- svelte-ignore a11y_no_static_element_interactions -->
 	<div
-		class="card-hover group rounded-xl {cardStyleClass} p-4 transition-colors hover:border-primary/50"
+		class="card-hover group rounded-[1.4rem] {cardStyleClass} p-4 transition-colors hover:border-primary/50"
 		data-app-widget
 		data-app-url={app.url}
 		oncontextmenu={handleContextMenu}
@@ -307,7 +307,7 @@
 			onclick={recordClick}
 		>
 			<div class="relative">
-				<div class="flex h-12 w-12 items-center justify-center rounded-lg bg-muted transition-colors group-hover:bg-accent">
+				<div class="flex h-12 w-12 items-center justify-center rounded-2xl bg-muted transition-colors group-hover:bg-accent">
 					{#if app.iconType === 'emoji' && app.icon}
 						<span class="text-2xl">{app.icon}</span>
 					{:else if iconSrc}
@@ -378,12 +378,12 @@
 <!-- Context Menu -->
 {#if showContextMenu}
 	<div
-		class="fixed z-50 rounded-lg border border-border bg-popover p-1 shadow-lg"
+		class="fixed z-50 rounded-2xl border border-border bg-popover p-1 shadow-[var(--shadow-soft)]"
 		style="left: {contextMenuPos.x}px; top: {contextMenuPos.y}px"
 	>
 		<button
 			type="button"
-			class="flex w-full items-center gap-2 rounded-sm px-3 py-1.5 text-sm text-popover-foreground transition-colors hover:bg-accent"
+			class="flex w-full items-center gap-2 rounded-xl px-3 py-2 text-sm text-popover-foreground transition-colors hover:bg-accent"
 			onclick={toggleFavorite}
 		>
 			{#if favorites.isFavorite(app.id)}