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/App.jsx

@@ -744,7 +744,7 @@ function AppContent() {
       {/* Fixed Desktop Sidebar */}
       {!isMobile && (
         <div
-          className={`flex-shrink-0 border-r border-border bg-card transition-all duration-300 ${
+          className={`h-full flex-shrink-0 border-r border-border bg-card transition-all duration-300 ${
             sidebarVisible ? 'w-80' : 'w-14'
           }`}
         >
@@ -837,11 +837,10 @@ function AppContent() {
             }}
             aria-label="Close sidebar"
           />
-          <div 
-            className={`relative w-[85vw] max-w-sm sm:w-80 bg-card border-r border-border transform transition-transform duration-150 ease-out ${
+          <div
+            className={`relative w-[85vw] max-w-sm sm:w-80 h-full bg-card border-r border-border transform transition-transform duration-150 ease-out ${
               sidebarOpen ? 'translate-x-0' : '-translate-x-full'
             }`}
-            style={{ height: 'calc(100vh - 80px)' }}
             onClick={(e) => e.stopPropagation()}
             onTouchStart={(e) => e.stopPropagation()}
           >

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">