Update README and moderation commands for localization and migration support

- Revised README to include database migration steps and a new section for database management.
- Enhanced moderation command responses to utilize localized messages for unknown commands.
- Refactored moderation commands to use centralized command data definitions, improving maintainability and consistency.
- Added localization support for command descriptions and options in both German and English.
- Versioned Prisma migrations for better tracking of database changes.

docs/DATABASE.md

@@ -0,0 +1,101 @@
+# Nexumi – Datenbank
+
+## Migrationen
+
+Prisma-Schema: `apps/bot/prisma/schema.prisma`
+
+Initiale Migration:
+
+- `apps/bot/prisma/migrations/20260722123000_init`
+
+### Lokale Entwicklung
+
+1. Stack starten:
+
+```bash
+docker compose up -d postgres redis
+```
+
+2. `.env` setzen (Beispiel lokal):
+
+```env
+DATABASE_URL=postgresql://nexumi:nexumi@localhost:5432/nexumi
+```
+
+Hinweis: Im Compose-Stack ist Postgres absichtlich nicht nach außen veröffentlicht. Für lokale Migrationen außerhalb von Docker entweder temporär einen Port mappen oder Migrationen im Bot-Container ausführen.
+
+3. Migration anwenden:
+
+```bash
+pnpm prisma:migrate
+```
+
+Alternativ im Bot-Container:
+
+```bash
+docker compose run --rm bot pnpm prisma:migrate
+```
+
+4. Client generieren:
+
+```bash
+pnpm prisma:generate
+```
+
+## Backup (automatisch)
+
+- Job: BullMQ `dailyPgDump`
+- Cron: `BACKUP_CRON` (Default `0 3 * * *`)
+- Zielverzeichnis: `BACKUP_DIR` (Default `/backups`)
+- Retention: `BACKUP_RETENTION_DAYS` (Default `14`)
+
+Backups liegen im Docker-Volume `backups`, am Bot-Container unter `/backups`.
+
+### Manuelles Backup
+
+```bash
+docker compose exec bot sh -c "pg_dump --dbname \"$DATABASE_URL\" --file /backups/manual-$(date -u +%Y%m%dT%H%M%SZ).sql"
+```
+
+## Restore
+
+1. Bot/WebUI stoppen:
+
+```bash
+docker compose stop bot webui
+```
+
+2. Backup-Datei in den Postgres-Container kopieren (Beispiel):
+
+```bash
+docker compose cp ./backups/nexumi-2026-07-22.sql postgres:/tmp/restore.sql
+```
+
+3. Restore ausführen:
+
+```bash
+docker compose exec -T postgres psql -U nexumi -d nexumi -f /tmp/restore.sql
+```
+
+4. Services wieder starten:
+
+```bash
+docker compose up -d
+```
+
+## Audit-Metadaten (Cases)
+
+Standardisierte Case-Metadaten werden zentral über `buildCaseMetadata()` in `@nexumi/shared` erzeugt.
+
+Pflichtfelder:
+
+- `source` (`slash_command`, `button_confirmation`, `escalation`, `job`)
+- `recordedAt` (ISO-Zeitstempel)
+
+Optionale Felder je nach Aktion:
+
+- `channelId`
+- `confirmed`
+- `escalation`, `warningCount`, `durationMs`
+- `purge.requestedAmount`, `purge.deletedCount`, `purge.filters`
+- `deletedCaseId`, `deletedCaseNumber`