fix: Gitea Traefik routing and connection pool optimization

- Remove middleware reference from Gitea Traefik labels (caused routing issues)
- Optimize Gitea connection pool settings (MAX_IDLE_CONNS=30, authentication_timeout=180s)
- Add explicit service reference in Traefik labels
- Fix intermittent 504 timeouts by improving PostgreSQL connection handling

Fixes Gitea unreachability via git.michaelschiemer.de

deployment/stacks/postgresql-production/README.md

@@ -0,0 +1,257 @@
+# PostgreSQL Production Stack - Production Database
+
+## Overview
+
+Production-ready PostgreSQL 16 database stack with automated backup system and performance optimization.
+
+**Features**:
+- PostgreSQL 16 Alpine (lightweight, secure)
+- Automated daily backups with configurable retention
+- Performance-optimized configuration (2GB memory allocation)
+- Health checks and automatic recovery
+- Persistent storage with named volumes
+- Isolated `postgres-production-internal` network
+- Resource limits for stability
+
+## Services
+
+- **postgres-production** - PostgreSQL 16 database server
+- **postgres-production-backup** - Automated backup service with cron scheduling
+
+## Prerequisites
+
+1. **Docker and Docker Compose** installed
+2. **Environment file** created (`.env`)
+
+## Configuration
+
+### 1. Create Environment File
+
+```bash
+cp .env.example .env
+```
+
+### 2. Generate Secure Password
+
+```bash
+openssl rand -base64 32
+```
+
+Update `.env`:
+```env
+POSTGRES_DB=michaelschiemer
+POSTGRES_USER=postgres
+POSTGRES_PASSWORD=<generated-password>
+BACKUP_RETENTION_DAYS=7
+BACKUP_SCHEDULE=0 2 * * *
+```
+
+## Deployment
+
+### Initial Setup
+
+```bash
+# Create environment file
+cp .env.example .env
+
+# Generate and set password
+openssl rand -base64 32
+# Update POSTGRES_PASSWORD in .env
+
+# Start services
+docker compose up -d
+
+# Check logs
+docker compose logs -f
+
+# Verify health
+docker compose ps
+```
+
+### Verify Deployment
+
+```bash
+# Check PostgreSQL is running
+docker exec postgres-production pg_isready -U postgres -d michaelschiemer
+
+# Expected: postgres-production:5432 - accepting connections
+
+# Check backup service
+docker compose logs postgres-production-backup
+
+# Expected: Initial backup completed successfully
+```
+
+## Integration with Production Application Stack
+
+The Production Application Stack connects to this database via the `postgres-production-internal` network.
+
+**Connection Configuration** in `deployment/stacks/production/.env`:
+```env
+DB_HOST=postgres-production
+DB_PORT=5432
+DB_DATABASE=michaelschiemer
+DB_USERNAME=postgres
+DB_PASSWORD=<same-as-postgres-production-password>
+```
+
+**Network Connection**: The Production Application Stack must be connected to the `postgres-production-internal` network.
+
+## Usage
+
+### Database Access
+
+#### From Host Machine
+
+```bash
+# Connect to database
+docker exec -it postgres-production psql -U postgres -d michaelschiemer
+
+# Run SQL query
+docker exec postgres-production psql -U postgres -d michaelschiemer -c "SELECT version();"
+```
+
+#### From Application Container
+
+```bash
+# Connection string format
+postgresql://postgres:password@postgres-production:5432/michaelschiemer
+```
+
+### Backup Management
+
+#### Manual Backup
+
+```bash
+# Trigger manual backup
+docker exec postgres-production-backup /scripts/backup.sh
+
+# List backups
+ls -lh backups/
+
+# Example output:
+# postgres_michaelschiemer_20250130_020000.sql.gz
+```
+
+#### Restore from Backup
+
+```bash
+# List available backups
+docker exec postgres-production-backup ls -lh /backups
+
+# Restore specific backup
+docker exec -it postgres-production-backup /scripts/restore.sh /backups/postgres_michaelschiemer_20250130_020000.sql.gz
+
+# ⚠️ WARNING: This will DROP and RECREATE the database!
+```
+
+## Network Isolation
+
+This stack uses its own isolated network:
+- **Network**: `postgres-production-internal`
+- **Purpose**: Isolate Production database from other services
+- **Access**: Only services explicitly connected to this network can access the database
+
+**Connecting Application Stack**:
+```yaml
+# In deployment/stacks/production/docker-compose.production.yml
+networks:
+  postgres-production-internal:
+    external: true
+    name: postgres-production-internal
+```
+
+## Security
+
+### Network Isolation
+- PostgreSQL only accessible via `postgres-production-internal` network
+- No external ports exposed
+- Service-to-service communication only
+
+### Authentication
+- Strong password required (generated with `openssl rand -base64 32`)
+- No default passwords
+- Password stored in environment variables only
+
+## Monitoring
+
+### Health Checks
+
+```bash
+# Check service health
+docker compose ps
+
+# Expected: Both services "healthy"
+
+# Manual health check
+docker exec postgres-production pg_isready -U postgres -d michaelschiemer
+```
+
+### Resource Usage
+
+```bash
+# Database container stats
+docker stats postgres-production --no-stream
+
+# Disk usage
+docker exec postgres-production du -sh /var/lib/postgresql/data
+```
+
+### Logs
+
+```bash
+# PostgreSQL logs
+docker compose logs postgres-production
+
+# Backup logs
+docker compose logs postgres-production-backup
+
+# Real-time monitoring
+docker compose logs -f
+```
+
+## Troubleshooting
+
+### Database Won't Start
+
+```bash
+# Check logs
+docker compose logs postgres-production
+
+# Common issues:
+# 1. Invalid configuration
+docker exec postgres-production postgres --check
+
+# 2. Permission issues
+docker exec postgres-production ls -la /var/lib/postgresql/data
+```
+
+### Connection Refused from Application
+
+```bash
+# 1. Check PostgreSQL is running
+docker compose ps postgres-production
+
+# 2. Verify network
+docker network inspect postgres-production-internal | grep postgres-production
+
+# 3. Check if application is connected to network
+docker network inspect postgres-production-internal | grep app
+```
+
+## Differences from Staging Stack
+
+| Aspect | Production | Staging |
+|--------|-----------|---------|
+| **Container Name** | postgres-production | postgres-staging |
+| **Network** | postgres-production-internal | postgres-staging-internal |
+| **Volume** | postgres-production-data | postgres-staging-data |
+| **Database** | michaelschiemer | michaelschiemer_staging |
+| **Backup Retention** | 7 days (configurable) | 7 days (configurable) |
+
+## Additional Resources
+
+- **PostgreSQL Documentation**: https://www.postgresql.org/docs/16/
+- **Performance Tuning**: https://wiki.postgresql.org/wiki/Performance_Optimization
+- **Backup Best Practices**: https://www.postgresql.org/docs/16/backup.html
+