feat: Nova UI component library + Studio dropdown/picker polish

- Add Nova UI library: Button, TextInput, Textarea, FormField, Select,
  NovaSelect, Checkbox, Radio/RadioGroup, Toggle, DatePicker,
  DateRangePicker, Modal + barrel index.js
- Replace all native <select> in Studio with NovaSelect (StudioFilters,
  StudioToolbar, BulkActionsBar) including frosted-glass portal and
  category group headers
- Replace native checkboxes in StudioGridCard, StudioTable, UploadSidebar,
  UploadWizard, Upload/Index with custom Checkbox component
- Add nova-scrollbar CSS utility (thin 4px, semi-transparent)
- Fix portal position drift: use viewport-relative coords (no scrollY offset)
  for NovaSelect, DatePicker and DateRangePicker
- Close portals on external scroll instead of remeasuring
- Improve hover highlight visibility in NovaSelect (bg-white/[0.13])
- Move search icon to right side in NovaSelect dropdown
- Reduce Studio layout top spacing (py-6 -> pt-4 pb-8)
- Add StudioCheckbox and SquareCheckbox backward-compat shims
- Add sync.sh rsync deploy script

resources/js/components/Studio/StudioTable.jsx

@@ -1,6 +1,7 @@
 import React from 'react'
 import StatusBadge from '../Badges/StatusBadge'
 import RisingBadge from '../Badges/RisingBadge'
+import Checkbox from '../ui/Checkbox'
 
 function getStatus(art) {
   if (art.deleted_at) return 'archived'
@@ -46,11 +47,10 @@ export default function StudioTable({ artworks, selectedIds, onSelect, onSelectA
         <thead className="sticky top-0 z-10 bg-nova-900/90 backdrop-blur-sm border-b border-white/10">
           <tr>
             <th className="p-3 w-10">
-              <input
-                type="checkbox"
+              <Checkbox
                 checked={allSelected}
                 onChange={onSelectAll}
-                className="w-4 h-4 rounded-sm bg-transparent border border-white/20 accent-accent focus:ring-accent/50 cursor-pointer"
+                aria-label="Select all artworks"
               />
             </th>
             <th className="p-3 w-12"></th>
@@ -74,11 +74,10 @@ export default function StudioTable({ artworks, selectedIds, onSelect, onSelectA
               className={`transition-colors ${selectedIds.includes(art.id) ? 'bg-accent/5' : 'hover:bg-white/[0.02]'}`}
             >
               <td className="p-3">
-                <input
-                  type="checkbox"
+                <Checkbox
                   checked={selectedIds.includes(art.id)}
                   onChange={() => onSelect(art.id)}
-                  className="w-4 h-4 rounded-sm bg-transparent border border-white/20 accent-accent focus:ring-accent/50 cursor-pointer"
+                  aria-label={`Select ${art.title}`}
                 />
               </td>
               <td className="p-3">