style(ui): remove inline styles in favor of Tailwind classes

Replace inline height calculations and conditional PWA padding with
standardized Tailwind utilities (h-full) for improved consistency and
maintainability. Simplifies responsive layout by removing device-
specific style adjustments while maintaining visual appearance.

src/components/Sidebar.jsx

@@ -467,7 +467,6 @@ function Sidebar({
 
       <div
         className="h-full flex flex-col bg-card md:select-none"
-        style={isPWA && isMobile ? { paddingTop: '44px' } : {}}
       >
       {/* Header */}
       <div className="md:p-4 md:border-b md:border-border">
@@ -501,11 +500,10 @@ function Sidebar({
             </Button>
           )}
         </div>
-        
+
         {/* Mobile Header */}
-        <div 
+        <div
           className="md:hidden p-3 border-b border-border"
-          style={isPWA && isMobile ? { paddingTop: '16px' } : {}}
         >
           <div className="flex items-center justify-between">
             <div className="flex items-center gap-3">