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/finance/src/server/api.ts

@@ -148,6 +148,59 @@ export function createFinanceApi(client: SupabaseClient<Database>) {
       return { ...data, items: items ?? [] };
     },
 
+    // --- SEPA auto-populate from members (Gap 3) ---
+    async populateBatchFromMembers(batchId: string, accountId: string) {
+      // Get all active members with active SEPA mandates + dues categories
+      const { data: members, error: memberError } = await client
+        .from('members')
+        .select('id, first_name, last_name, dues_category_id')
+        .eq('account_id', accountId)
+        .eq('status', 'active');
+      if (memberError) throw memberError;
+
+      const { data: mandates, error: mandateError } = await client
+        .from('sepa_mandates')
+        .select('*')
+        .eq('account_id', accountId)
+        .eq('status', 'active')
+        .eq('is_primary', true);
+      if (mandateError) throw mandateError;
+
+      const { data: categories, error: catError } = await client
+        .from('dues_categories')
+        .select('id, amount')
+        .eq('account_id', accountId);
+      if (catError) throw catError;
+
+      const mandateMap = new Map((mandates ?? []).map((m: any) => [m.member_id, m]));
+      const categoryMap = new Map((categories ?? []).map((c: any) => [c.id, Number(c.amount)]));
+
+      let addedCount = 0;
+      for (const member of (members ?? []) as any[]) {
+        const mandate = mandateMap.get(member.id);
+        if (!mandate) continue;
+
+        const amount = member.dues_category_id ? categoryMap.get(member.dues_category_id) ?? 0 : 0;
+        if (amount <= 0) continue;
+
+        const { error } = await client.from('sepa_items').insert({
+          batch_id: batchId,
+          member_id: member.id,
+          debtor_name: `${member.first_name} ${member.last_name}`,
+          debtor_iban: mandate.iban,
+          debtor_bic: mandate.bic,
+          amount,
+          mandate_id: mandate.mandate_reference,
+          mandate_date: mandate.mandate_date,
+          remittance_info: `Mitgliedsbeitrag ${new Date().getFullYear()}`,
+        });
+        if (!error) addedCount++;
+      }
+
+      await this.recalculateBatchTotals(batchId);
+      return { addedCount };
+    },
+
     // --- Utilities ---
     validateIban,
   };