Restyle dark theme with blue-tinted palette, card glow, and rounded surfaces

Shift the dark theme from neutral gray to a richer blue-tinted palette
inspired by CharBuilder-style TTRPG apps. Deeper navy background, steel-blue
card surfaces, and visible blue borders create more depth and visual layering.

- Update design tokens: background, card, border, input, muted colors
- Add card-glow utility (radial gradient + blue box-shadow) for card surfaces
- Add panel-glow utility (top-down gradient) for tall panels like stat blocks
- Apply glow and rounded-lg to all card surfaces, dropdowns, dialogs, toasts
- Give outline buttons a subtle fill instead of transparent background
- Active combatant row now uses full border with glow instead of left accent

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

apps/web/src/components/toast.tsx

@@ -24,7 +24,7 @@ export function Toast({
 
 	return createPortal(
 		<div className="fixed bottom-4 left-4 z-50">
-			<div className="flex items-center gap-3 rounded-lg border border-border bg-card px-4 py-3 shadow-lg">
+			<div className="card-glow flex items-center gap-3 rounded-lg border border-border bg-card px-4 py-3">
 				<span className="text-foreground text-sm">{message}</span>
 				{progress !== undefined && (
 					<div className="h-2 w-24 overflow-hidden rounded-full bg-muted">