feat: unified glass material system for all floating surfaces

Add .glass-modal CSS class (0.82 opacity) for dialogs and apply
consistent glass tiers across all floating UI: modals, context menus,
tooltips, popovers, and call cards. Replaces ad-hoc bg-surface-elevated
and inline styles with the documented 5-tier glass hierarchy.

packages/web/src/components/ui/Tooltip.tsx

@@ -43,7 +43,7 @@ export function Tooltip({ content, children, position = 'right', delay = 200 }:
         <div
           ref={floatingRef}
           style={style}
-          className="px-3 py-1.5 text-sm font-medium text-txt-primary bg-surface-elevated rounded-md shadow-elevation-high whitespace-nowrap pointer-events-none"
+          className="px-3 py-1.5 text-sm font-medium text-txt-primary glass rounded-md whitespace-nowrap pointer-events-none"
         >
           {content}
         </div>,