fix: use admin theme CSS variables in upload-furni-client

Replace hardcoded border-gray-300 and text-yellow-* classes
with semantic admin theme tokens (border-input, --admin-warning).

src/app/admin/import/furni/upload/upload-furni-client.tsx

@@ -197,7 +197,7 @@ export function UploadFurniClient() {
 									type="checkbox"
 									checked={canstandon}
 									onChange={(e) => setCanstandon(e.target.checked)}
-									className="h-4 w-4 rounded border-gray-300"
+									className="h-4 w-4 rounded border-input"
 								/>
 								<span className="text-sm">Can stand on</span>
 							</label>
@@ -206,7 +206,7 @@ export function UploadFurniClient() {
 									type="checkbox"
 									checked={cansiton}
 									onChange={(e) => setCansiton(e.target.checked)}
-									className="h-4 w-4 rounded border-gray-300"
+									className="h-4 w-4 rounded border-input"
 								/>
 								<span className="text-sm">Can sit on</span>
 							</label>
@@ -215,7 +215,7 @@ export function UploadFurniClient() {
 									type="checkbox"
 									checked={canlayon}
 									onChange={(e) => setCanlayon(e.target.checked)}
-									className="h-4 w-4 rounded border-gray-300"
+									className="h-4 w-4 rounded border-input"
 								/>
 								<span className="text-sm">Can lay on</span>
 							</label>
@@ -312,7 +312,7 @@ export function UploadFurniClient() {
 								{result.warnings.map((w) => (
 									<div
 										key={w}
-										className="flex items-center gap-1.5 text-yellow-600 dark:text-yellow-400"
+										className="flex items-center gap-1.5 text-[var(--admin-warning)] dark:text-[var(--admin-warning)]"
 									>
 										<AlertCircle className="w-3 h-3 shrink-0" />
 										<span>{w}</span>