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/hp-adjust-popover.tsx

@@ -87,7 +87,7 @@ export function HpAdjustPopover({ onAdjust, onClose }: HpAdjustPopoverProps) {
 	return (
 		<div
 			ref={ref}
-			className="fixed z-10 rounded-md border border-border bg-background p-2 shadow-lg"
+			className="card-glow fixed z-10 rounded-lg border border-border bg-background p-2"
 			style={
 				pos
 					? { top: pos.top, left: pos.left }