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/combatant-row.tsx

@@ -365,7 +365,7 @@ function rowBorderClass(
 	isActive: boolean,
 	isConcentrating: boolean | undefined,
 ): string {
-	if (isActive) return "border-l-2 border-l-accent bg-accent/10";
+	if (isActive) return "border border-accent/40 bg-accent/10 card-glow";
 	if (isConcentrating) return "border-l-2 border-l-purple-400";
 	return "border-l-2 border-l-transparent";
 }
@@ -434,7 +434,7 @@ export function CombatantRow({
 		<div
 			ref={ref}
 			className={cn(
-				"group rounded-md pr-3 transition-colors",
+				"group rounded-lg pr-3 transition-colors",
 				rowBorderClass(isActive, combatant.isConcentrating),
 				isPulsing && "animate-concentration-pulse",
 			)}