feat: wire 10 dead buttons across 6 modules to their server actions

Every module had buttons that rendered visually but did nothing when
clicked. Server actions existed for all of them. Created client
components with dialogs/forms and wired them in.

BOOKINGS MODULE:
- BookingStatusActions: Check-in/Check-out/Cancel buttons now call
  updateBookingStatus server action with loading states + toast
- CreateRoomDialog: 'Neues Zimmer' opens dialog with room number,
  name, capacity, price/night fields → calls createRoom
- CreateGuestDialog: 'Neuer Gast' opens dialog with first/last name,
  email, phone fields → calls createGuest

COURSES MODULE:
- EnrollParticipantDialog: 'Teilnehmer anmelden' on participants
  page opens dialog with first/last name, email, phone → calls
  enrollParticipant

EVENTS MODULE:
- EventRegistrationDialog: 'Anmeldung' button on event detail opens
  dialog with participant data + DOB → calls registerForEvent
- CreateHolidayPassDialog: 'Neuer Ferienpass' opens dialog with name,
  year, description, price, date range → calls createHolidayPass

NEWSLETTER MODULE:
- CreateTemplateDialog: 'Neue Vorlage' opens dialog with name,
  subject, HTML body → calls createTemplate

SITE-BUILDER MODULE:
- Posts 'Neuer Beitrag' button now links to /posts/new page

All dialogs use German labels, helpful placeholders, loading spinners,
toast notifications, and form validation appropriate for association
board members (Vereinsvorstände, 40-65, moderate tech skills).

apps/web/app/[locale]/home/[account]/bookings/[bookingId]/page.tsx

@@ -4,13 +4,11 @@ import {
   ArrowLeft,
   BedDouble,
   CalendarDays,
-  LogIn,
-  LogOut,
-  XCircle,
   User,
 } from 'lucide-react';
 import { getTranslations } from 'next-intl/server';
 
+import { BookingStatusActions } from '@kit/booking-management/components';
 import { formatDate, formatCurrencyAmount } from '@kit/shared/dates';
 import { getSupabaseServerClient } from '@kit/supabase/server-client';
 import { Badge } from '@kit/ui/badge';
@@ -288,41 +286,10 @@ export default async function BookingDetailPage({ params }: PageProps) {
             <CardDescription>{t('detail.changeStatus')}</CardDescription>
           </CardHeader>
           <CardContent>
-            <div className="flex flex-wrap gap-3">
-              {(status === 'pending' || status === 'confirmed') && (
-                <Button variant="default">
-                  <LogIn className="mr-2 h-4 w-4" />
-                  {t('detail.checkIn')}
-                </Button>
-              )}
-
-              {status === 'checked_in' && (
-                <Button variant="default">
-                  <LogOut className="mr-2 h-4 w-4" />
-                  {t('detail.checkOut')}
-                </Button>
-              )}
-
-              {status !== 'cancelled' &&
-                status !== 'checked_out' &&
-                status !== 'no_show' && (
-                  <Button variant="destructive">
-                    <XCircle className="mr-2 h-4 w-4" />
-                    {t('detail.cancel')}
-                  </Button>
-                )}
-
-              {status === 'cancelled' || status === 'checked_out' ? (
-                <p className="text-muted-foreground py-2 text-sm">
-                  {t('detail.noMoreActions', {
-                    statusLabel:
-                      status === 'cancelled'
-                        ? t('detail.cancelledStatus')
-                        : t('detail.completedStatus'),
-                  })}
-                </p>
-              ) : null}
-            </div>
+            <BookingStatusActions
+              bookingId={bookingId}
+              status={status}
+            />
           </CardContent>
         </Card>
       </div>

apps/web/app/[locale]/home/[account]/bookings/guests/page.tsx

@@ -2,6 +2,7 @@ import { UserCircle, Plus } from 'lucide-react';
 import { getTranslations } from 'next-intl/server';
 
 import { createBookingManagementApi } from '@kit/booking-management/api';
+import { CreateGuestDialog } from '@kit/booking-management/components';
 import { getSupabaseServerClient } from '@kit/supabase/server-client';
 import { Button } from '@kit/ui/button';
 import { Card, CardContent, CardHeader, CardTitle } from '@kit/ui/card';
@@ -41,10 +42,7 @@ export default async function GuestsPage({ params }: PageProps) {
       <div className="flex w-full flex-col gap-6">
         <div className="flex items-center justify-between">
           <p className="text-muted-foreground">{t('guests.manage')}</p>
-          <Button data-test="guests-new-btn">
-            <Plus className="mr-2 h-4 w-4" />
-            {t('guests.newGuest')}
-          </Button>
+          <CreateGuestDialog accountId={acct.id} />
         </div>
 
         {guests.length === 0 ? (

apps/web/app/[locale]/home/[account]/bookings/rooms/page.tsx

@@ -2,6 +2,7 @@ import { BedDouble, Plus } from 'lucide-react';
 import { getTranslations } from 'next-intl/server';
 
 import { createBookingManagementApi } from '@kit/booking-management/api';
+import { CreateRoomDialog } from '@kit/booking-management/components';
 import { formatCurrencyAmount } from '@kit/shared/dates';
 import { getSupabaseServerClient } from '@kit/supabase/server-client';
 import { Badge } from '@kit/ui/badge';
@@ -43,10 +44,7 @@ export default async function RoomsPage({ params }: PageProps) {
       <div className="flex w-full flex-col gap-6">
         <div className="flex items-center justify-between">
           <p className="text-muted-foreground">{t('rooms.manage')}</p>
-          <Button data-test="rooms-new-btn">
-            <Plus className="mr-2 h-4 w-4" />
-            {t('rooms.newRoom')}
-          </Button>
+          <CreateRoomDialog accountId={acct.id} />
         </div>
 
         {rooms.length === 0 ? (

apps/web/app/[locale]/home/[account]/courses/[courseId]/participants/page.tsx

@@ -2,6 +2,7 @@ import { Plus, Users } from 'lucide-react';
 import { getTranslations } from 'next-intl/server';
 
 import { createCourseManagementApi } from '@kit/course-management/api';
+import { EnrollParticipantDialog } from '@kit/course-management/components';
 import { formatDate } from '@kit/shared/dates';
 import { getSupabaseServerClient } from '@kit/supabase/server-client';
 import { Badge } from '@kit/ui/badge';
@@ -56,10 +57,7 @@ export default async function ParticipantsPage({ params }: PageProps) {
               {participants.length} {t('participants.title')}
             </p>
           </div>
-          <Button data-test="participants-add-btn">
-            <Plus className="mr-2 h-4 w-4" />
-            {t('participants.add')}
-          </Button>
+          <EnrollParticipantDialog courseId={courseId} />
         </div>
 
         {participants.length === 0 ? (

apps/web/app/[locale]/home/[account]/events/[eventId]/page.tsx

@@ -11,6 +11,7 @@ import {
 import { getTranslations } from 'next-intl/server';
 
 import { createEventManagementApi } from '@kit/event-management/api';
+import { EventRegistrationDialog } from '@kit/event-management/components';
 import { formatDate } from '@kit/shared/dates';
 import { getSupabaseServerClient } from '@kit/supabase/server-client';
 import { Badge } from '@kit/ui/badge';
@@ -73,10 +74,7 @@ export default async function EventDetailPage({ params }: PageProps) {
               )}
             </Badge>
           </div>
-          <Button>
-            <UserPlus className="mr-2 h-4 w-4" />
-            {t('register')}
-          </Button>
+          <EventRegistrationDialog eventId={eventId} eventName={String((event as any).name ?? '')} />
         </div>
 
         {/* Detail Cards */}

apps/web/app/[locale]/home/[account]/events/holiday-passes/page.tsx

@@ -2,6 +2,7 @@ import { Ticket, Plus } from 'lucide-react';
 import { getTranslations } from 'next-intl/server';
 
 import { createEventManagementApi } from '@kit/event-management/api';
+import { CreateHolidayPassDialog } from '@kit/event-management/components';
 import { formatDate, formatCurrencyAmount } from '@kit/shared/dates';
 import { getSupabaseServerClient } from '@kit/supabase/server-client';
 import { Button } from '@kit/ui/button';
@@ -40,10 +41,7 @@ export default async function HolidayPassesPage({ params }: PageProps) {
               {t('holidayPassesDescription')}
             </p>
           </div>
-          <Button>
-            <Plus className="mr-2 h-4 w-4" />
-            {t('newHolidayPass')}
-          </Button>
+          <CreateHolidayPassDialog accountId={acct.id} />
         </div>
 
         {passes.length === 0 ? (

apps/web/app/[locale]/home/[account]/newsletter/templates/page.tsx

@@ -2,6 +2,7 @@ import { FileText, Plus } from 'lucide-react';
 import { getTranslations } from 'next-intl/server';
 
 import { createNewsletterApi } from '@kit/newsletter/api';
+import { CreateTemplateDialog } from '@kit/newsletter/components';
 import { getSupabaseServerClient } from '@kit/supabase/server-client';
 import { Badge } from '@kit/ui/badge';
 import { Button } from '@kit/ui/button';
@@ -41,10 +42,7 @@ export default async function NewsletterTemplatesPage({ params }: PageProps) {
             <p className="text-muted-foreground">{t('templates.subtitle')}</p>
           </div>
 
-          <Button data-test="newsletter-templates-new-btn">
-            <Plus className="mr-2 h-4 w-4" />
-            {t('templates.newTemplate')}
-          </Button>
+          <CreateTemplateDialog accountId={acct.id} />
         </div>
 
         {/* Table or Empty State */}

apps/web/app/[locale]/home/[account]/site-builder/posts/page.tsx

@@ -1,3 +1,5 @@
+import Link from 'next/link';
+
 import { Plus } from 'lucide-react';
 import { getTranslations } from 'next-intl/server';
 
@@ -45,9 +47,11 @@ export default async function PostsManagerPage({ params }: Props) {
     >
       <div className="space-y-6">
         <div className="flex justify-end">
-          <Button data-test="site-new-post-btn">
-            <Plus className="mr-2 h-4 w-4" />
-            {t('posts.newPost')}
+          <Button data-test="site-new-post-btn" asChild>
+            <Link href={`/home/${account}/site-builder/posts/new`}>
+              <Plus className="mr-2 h-4 w-4" />
+              {t('posts.newPost')}
+            </Link>
           </Button>
         </div>
         {posts.length === 0 ? (