chore: fix all Biome lint warnings and MedDetail intake bell icons (#265)

- Backend: refactor nested ternaries, remove unused imports/any types
- Frontend: fix exhaustive deps, a11y label associations, array index keys,
  empty CSS blocks, unused vars, type annotations
- MedDetail modal: fix intake schedule bell icons not rendering (use unified
  intake source with fallback), place bell inline after person name
- MedDetail modal: revert schedule rows from grid to flexbox layout

Closes #264

frontend/src/components/Lightbox.tsx

@@ -31,7 +31,15 @@ export function Lightbox({ src, alt, onClose }: LightboxProps) {
 	}
 
 	return (
-		<div className="lightbox-overlay" onClick={handleOverlayClick}>
+		<div
+			className="lightbox-overlay"
+			onClick={handleOverlayClick}
+			onKeyDown={(e) => {
+				if (e.key === "Escape") {
+					onClose();
+				}
+			}}
+		>
 			<div className="lightbox-container">
 				<button className="lightbox-close" onClick={onClose}>
 					×