Add Docker support and fix external access issues

🐳 Docker Configuration:
- Created Dockerfile for containerized API deployment
- Added docker-compose.api.yml for complete stack
- Added requirements.txt for Docker builds
- Added .dockerignore for optimized builds
- Configured external access on 0.0.0.0:8080

📚 Documentation Updates:
- Updated quickstart to reflect Neo4j already running
- Added Docker deployment tabs with external access info
- Updated REST API docs with Docker deployment options
- Clarified local vs external access deployment methods

🔧 Configuration:
- API_HOST=0.0.0.0 for external access in Docker
- Health checks and restart policies
- Proper networking and volume configuration
- Environment variable configuration

✅ Addresses user issues:
- REST API now accessible from outside the machine via Docker
- Documentation reflects actual infrastructure state
- Clear deployment options for different use cases

🤖 Generated with [Claude Code](https://claude.ai/code)

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

docs/open-source/features/rest-api.mdx

@@ -68,14 +68,34 @@ Mem0 provides a comprehensive REST API server built with FastAPI. The implementa
         ```
     </Tab>
 
-    <Tab title="With Docker (Future)">
-        Docker support is planned for Phase 3.
+    <Tab title="With Docker ✅ Recommended for External Access">
+        For external access and production deployment:
 
         ```bash
-        # Coming soon in Phase 3
-        docker build -t mem0-api-server .
-        docker run -p 8080:8080 mem0-api-server
+        # Using Docker Compose (recommended)
+        docker-compose -f docker-compose.api.yml up -d
         ```
+
+        Or build and run manually:
+
+        ```bash
+        # Build the image
+        docker build -t mem0-api-server .
+
+        # Run with external access
+        docker run -d \
+          --name mem0-api \
+          -p 8080:8080 \
+          -e API_HOST=0.0.0.0 \
+          -e API_PORT=8080 \
+          mem0-api-server
+        ```
+
+        **Access:** http://YOUR_SERVER_IP:8080 (accessible from external networks)
+        
+        <Note>
+        The Docker deployment automatically configures external access on `0.0.0.0:8080`.
+        </Note>
     </Tab>
 </Tabs>