Initial: Docker-Compose-Stack für Rapport Self-Hosting

Komplettes Bundle für eigene Rapport-Instanz:
- Postgres mit Supabase-Extensions + Init-Script für Standard-Rollen
- GoTrue (Auth) mit konfigurierbarem SMTP für Passwort-Reset-Mails
- PostgREST (REST-API)
- Realtime (Postgres-Changes für Live-Sync)
- Storage-API (Bilder/Quittungen)
- Kong als API-Gateway
- Rapport-Frontend als Multi-Stage-Build (zieht Sources aus dem App-Repo)

Plus:
- scripts/sync-migrations.sh: holt SQL aus dem App-Repo
- .env.example mit allen Pflicht-Secrets + optionalen SMTP-Werten
- nginx.conf mit SPA-Routing
- README mit Setup-Anleitung (Linux + macOS-Colima)
- LICENSE (AGPL-3.0)

Sync mit App-Repo: scripts/sync-migrations.sh holt die Migrations-SQL via
git clone und legt sie nach volumes/db/init/migrations/. Bei jedem
Rapport-Update erneut ausführen.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

LICENSE

@@ -0,0 +1,24 @@
+Rapport-Server — Self-Hosting-Stack für Rapport
+Copyright (C) 2026 Karim Gabriele Varano
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU Affero General Public License as published
+by the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU Affero General Public License for more details.
+
+You should have received a copy of the GNU Affero General Public License
+along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+────────────────────────────────────────────────────────────────────────
+
+Full license text: https://www.gnu.org/licenses/agpl-3.0.txt
+
+The bundled Supabase containers (postgres, gotrue, postgrest, realtime,
+storage-api, kong, supabase/postgres image) are distributed under their
+own permissive licenses (mostly Apache-2.0 and PostgreSQL License) by the
+Supabase team. See https://supabase.com/docs/guides/self-hosting for details.