refactor: CSS utility tridy + slouceni badge souboru

- pridano 20 utility trid (flex-1, mb-2, text-right, fw-500, admin-spinner-sm, atd.)
- nahrazeno ~100 opakovanych inline stylu ve 39 JSX souborech
- slouceno leave.css, orders.css, projects.css do admin.css (status badges)
- bundle size: 228.91 -> 228.43 kB (-0.48 kB)

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/admin/pages/Vehicles.jsx

@@ -183,8 +183,8 @@ export default function Vehicles() {
             {[0, 1, 2, 3, 4].map(i => (
               <div key={i} className="admin-skeleton-row">
                 <div className="admin-skeleton-line circle" />
-                <div style={{ flex: 1 }}>
-                  <div className="admin-skeleton-line w-1/3" style={{ marginBottom: '0.5rem' }} />
+                <div className="flex-1">
+                  <div className="admin-skeleton-line w-1/3 mb-2" />
                   <div className="admin-skeleton-line w-1/4" style={{ height: '10px' }} />
                 </div>
                 <div className="admin-skeleton-line w-1/4" />
@@ -259,7 +259,7 @@ export default function Vehicles() {
                 <tbody>
                   {vehicles.map((vehicle) => (
                     <tr key={vehicle.id} className={!vehicle.is_active ? 'admin-table-row-inactive' : ''}>
-                      <td className="admin-mono" style={{ fontWeight: 500 }}>{vehicle.spz}</td>
+                      <td className="admin-mono fw-500">{vehicle.spz}</td>
                       <td>{vehicle.name}</td>
                       <td>
                         {vehicle.brand || vehicle.model
@@ -267,7 +267,7 @@ export default function Vehicles() {
                           : '—'}
                       </td>
                       <td className="admin-mono">{formatKm(vehicle.initial_km)} km</td>
-                      <td className="admin-mono" style={{ fontWeight: 500 }}>{formatKm(vehicle.current_km)} km</td>
+                      <td className="admin-mono fw-500">{formatKm(vehicle.current_km)} km</td>
                       <td className="admin-mono">{vehicle.trip_count}</td>
                       <td>
                         <button