refactor(ui): replace inline INPUT_CLS/LABEL_CLS/BTN_DANGER constants and action link classes with CSS component classes

Remove duplicated Tailwind class string constants from 15 component files.
Use app-input, app-select, app-label, app-action-danger-btn, and
app-action-delete CSS component classes from globals.css instead.

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

apps/web/src/components/vacations/HolidayCalendarEditor.tsx

@@ -831,7 +831,7 @@ export function HolidayCalendarEditor() {
                                 type="button"
                                 onClick={() => handleDeleteEntry(entry)}
                                 disabled={deleteEntry.isPending}
-                                className="text-xs font-medium text-red-600 hover:text-red-700"
+                                className="app-action-delete"
                               >
                                 Entfernen
                               </button>