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/routes/login/+page.svelte

@@ -19,11 +19,11 @@
 <AmbientBackground />
 
 <main class="relative z-10 flex min-h-screen items-center justify-center bg-background/80 p-4 text-foreground">
-	<div class="w-full max-w-md rounded-xl border border-border bg-card/90 p-8 shadow-xl backdrop-blur-sm">
+	<div class="w-full max-w-md rounded-[1.6rem] border border-border bg-card/90 p-8 shadow-[var(--shadow-lift)] backdrop-blur-sm">
 		<div class="mb-8 text-center">
-			<div class="mx-auto mb-3 flex h-12 w-12 items-center justify-center rounded-lg bg-primary/10">
+			<div class="mx-auto mb-3 flex h-14 w-14 items-center justify-center rounded-2xl text-primary-foreground shadow-[var(--shadow-soft)]" style="background: linear-gradient(135deg, var(--room-peach), var(--room-terra));">
 				<svg
-					class="h-6 w-6 text-primary"
+					class="h-7 w-7"
 					xmlns="http://www.w3.org/2000/svg"
 					viewBox="0 0 24 24"
 					fill="none"
@@ -45,7 +45,7 @@
 		{#if showOAuthButton}
 			<a
 				href="/auth/oauth/authorize"
-				class="flex w-full items-center justify-center gap-2 rounded-lg border border-border bg-background px-4 py-2.5 text-sm font-medium text-foreground transition-colors hover:bg-muted focus:outline-none focus:ring-2 focus:ring-ring"
+				class="flex w-full items-center justify-center gap-2 rounded-xl border border-border bg-background px-4 py-2.5 text-sm font-semibold text-foreground transition-colors hover:bg-muted focus:outline-none focus-visible:ring-2 focus-visible:ring-primary/30"
 			>
 				<svg class="h-5 w-5" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round">
 					<path d="M15 3h4a2 2 0 0 1 2 2v14a2 2 0 0 1-2 2h-4" />
@@ -79,7 +79,7 @@
 						type="email"
 						autocomplete="email"
 						bind:value={$form.email}
-						class="w-full rounded-lg border border-input bg-background px-3 py-2.5 text-sm text-foreground placeholder:text-muted-foreground transition-colors focus:border-primary focus:outline-none focus:ring-2 focus:ring-ring/30"
+						class="w-full rounded-xl border border-input bg-background px-3 py-2.5 text-sm text-foreground placeholder:text-muted-foreground transition-colors focus:border-primary focus:outline-none focus-visible:ring-2 focus-visible:ring-primary/30"
 						placeholder={$t('auth.email_placeholder')}
 					/>
 					{#if $errors.email}
@@ -97,7 +97,7 @@
 						type="password"
 						autocomplete="current-password"
 						bind:value={$form.password}
-						class="w-full rounded-lg border border-input bg-background px-3 py-2.5 text-sm text-foreground placeholder:text-muted-foreground transition-colors focus:border-primary focus:outline-none focus:ring-2 focus:ring-ring/30"
+						class="w-full rounded-xl border border-input bg-background px-3 py-2.5 text-sm text-foreground placeholder:text-muted-foreground transition-colors focus:border-primary focus:outline-none focus-visible:ring-2 focus-visible:ring-primary/30"
 						placeholder={$t('auth.password_placeholder')}
 					/>
 					{#if $errors.password}
@@ -111,7 +111,7 @@
 							type="checkbox"
 							name="rememberMe"
 							bind:checked={$form.rememberMe}
-							class="h-4 w-4 rounded border-input text-primary focus:ring-2 focus:ring-ring/30"
+							class="h-4 w-4 rounded border-input text-primary focus-visible:ring-2 focus-visible:ring-primary/30"
 						/>
 						<span>{$t('auth.remember_me')}</span>
 					</label>
@@ -123,7 +123,7 @@
 				<button
 					type="submit"
 					disabled={$submitting}
-					class="w-full rounded-lg bg-primary px-4 py-2.5 text-sm font-medium text-primary-foreground transition-colors hover:bg-primary/90 focus:outline-none focus:ring-2 focus:ring-ring disabled:cursor-not-allowed disabled:opacity-50"
+					class="w-full rounded-xl bg-primary px-4 py-2.5 text-sm font-semibold text-primary-foreground shadow-[var(--shadow-soft)] transition-all hover:-translate-y-0.5 hover:bg-primary/90 focus:outline-none focus-visible:ring-2 focus-visible:ring-primary/30 disabled:cursor-not-allowed disabled:opacity-50"
 				>
 					{#if $submitting}
 						<span class="flex items-center justify-center gap-2">