feat: MyEasyCMS v2 — Full SaaS rebuild

Complete rebuild of 22-year-old PHP CMS as modern SaaS:

Database (15 migrations, 42+ tables):
- Foundation: account_settings, audit_log, GDPR register, cms_files
- Module Engine: modules, fields, records, permissions, relations + RPC
- Members: 45+ field member profiles, departments, roles, honors, SEPA mandates
- Courses: courses, sessions, categories, instructors, locations, attendance
- Bookings: rooms, guests, bookings with availability
- Events: events, registrations, holiday passes
- Finance: SEPA batches/items (pain.008/001 XML), invoices
- Newsletter: campaigns, templates, recipients, subscriptions
- Site Builder: site_pages (Puck JSON), site_settings, cms_posts
- Portal Auth: member_portal_invitations, user linking

Feature Packages (9):
- @kit/module-builder — dynamic low-code CRUD engine
- @kit/member-management — 31 API methods, 21 actions, 8 components
- @kit/course-management, @kit/booking-management, @kit/event-management
- @kit/finance — SEPA XML generator + IBAN validator
- @kit/newsletter — campaigns + dispatch
- @kit/document-generator — PDF/Excel/Word
- @kit/site-builder — Puck visual editor, 15 blocks, public rendering

Pages (60+):
- Dashboard with real stats from all APIs
- Full CRUD for all 8 domains with react-hook-form + Zod
- Recharts statistics
- German i18n throughout
- Member portal with auth + invitation system
- Public club websites via Puck at /club/[slug]

Infrastructure:
- Dockerfile (multi-stage, standalone output)
- docker-compose.yml (Supabase self-hosted + Next.js)
- Kong API gateway config
- .env.production.example

packages/features/newsletter/src/server/actions/newsletter-actions.ts

@@ -0,0 +1,91 @@
+'use server';
+
+import { z } from 'zod';
+import { authActionClient } from '@kit/next/safe-action';
+import { getLogger } from '@kit/shared/logger';
+import { getSupabaseServerClient } from '@kit/supabase/server-client';
+import {
+  CreateNewsletterSchema,
+  CreateTemplateSchema,
+} from '../../schema/newsletter.schema';
+import { createNewsletterApi } from '../api';
+
+export const createNewsletter = authActionClient
+  .inputSchema(CreateNewsletterSchema)
+  .action(async ({ parsedInput: input, ctx }) => {
+    const client = getSupabaseServerClient();
+    const logger = await getLogger();
+    const api = createNewsletterApi(client);
+    const userId = ctx.user.id;
+
+    logger.info({ name: 'newsletter.create' }, 'Creating newsletter...');
+    const result = await api.createNewsletter(input, userId);
+    logger.info({ name: 'newsletter.create' }, 'Newsletter created');
+    return { success: true, data: result };
+  });
+
+export const createTemplate = authActionClient
+  .inputSchema(
+    z.object({
+      accountId: z.string().uuid(),
+      name: z.string().min(1),
+      subject: z.string().min(1),
+      bodyHtml: z.string().min(1),
+      bodyText: z.string().optional(),
+      variables: z.array(z.string()).optional(),
+    }),
+  )
+  .action(async ({ parsedInput: input, ctx }) => {
+    const client = getSupabaseServerClient();
+    const logger = await getLogger();
+    const api = createNewsletterApi(client);
+
+    logger.info({ name: 'newsletter.createTemplate' }, 'Creating template...');
+    const result = await api.createTemplate(input);
+    logger.info({ name: 'newsletter.createTemplate' }, 'Template created');
+    return { success: true, data: result };
+  });
+
+export const addRecipients = authActionClient
+  .inputSchema(
+    z.object({
+      newsletterId: z.string().uuid(),
+      accountId: z.string().uuid(),
+      filter: z
+        .object({
+          status: z.array(z.string()).optional(),
+        })
+        .optional(),
+    }),
+  )
+  .action(async ({ parsedInput: input, ctx }) => {
+    const client = getSupabaseServerClient();
+    const logger = await getLogger();
+    const api = createNewsletterApi(client);
+
+    logger.info({ name: 'newsletter.addRecipients' }, 'Adding recipients...');
+    const result = await api.addRecipientsFromMembers(
+      input.newsletterId,
+      input.accountId,
+      input.filter,
+    );
+    logger.info({ name: 'newsletter.addRecipients' }, 'Recipients added');
+    return { success: true, data: result };
+  });
+
+export const dispatchNewsletter = authActionClient
+  .inputSchema(
+    z.object({
+      newsletterId: z.string().uuid(),
+    }),
+  )
+  .action(async ({ parsedInput: input, ctx }) => {
+    const client = getSupabaseServerClient();
+    const logger = await getLogger();
+    const api = createNewsletterApi(client);
+
+    logger.info({ name: 'newsletter.dispatch' }, 'Dispatching newsletter...');
+    const result = await api.dispatch(input.newsletterId);
+    logger.info({ name: 'newsletter.dispatch' }, 'Newsletter dispatched');
+    return { success: true, data: result };
+  });