ota: add ota update capabilities

README.md

@@ -135,6 +135,14 @@ GPIO pins can be configured in `main/config.h`. Modify the `bmc_gpio_defaults` a
 | GET | `/api/system/info` | Get system information |
 | GET | `/api/system/status` | Get BMC status |
 
+### OTA Endpoints
+
+| Method | Endpoint | Description |
+|--------|----------|-------------|
+| GET | `/api/ota/status` | Get OTA status and running partition |
+| POST | `/api/ota/update` | Start OTA update from URL |
+| POST | `/api/ota/upload` | Upload firmware file directly |
+
 ## Web Interface
 
 Access the web interface by navigating to `http://<ip-address>/` in your browser.
@@ -144,6 +152,7 @@ Features:
 - Real-time GPIO monitoring
 - Serial console with WebSocket support
 - System information display
+- OTA firmware update
 
 ## Example Usage
 
@@ -175,11 +184,30 @@ ws.onmessage = (event) => console.log(event.data);
 ws.send('command\n');
 ```
 
+### OTA Firmware Update
+
+```bash
+# Check OTA status
+curl http://192.168.1.100/api/ota/status
+
+# Start OTA update from URL
+curl -X POST http://192.168.1.100/api/ota/update \
+  -H "Content-Type: application/json" \
+  -d '{"url": "http://server/firmware.bin"}'
+
+# Upload firmware file directly
+curl -X POST http://192.168.1.100/api/ota/upload \
+  -F "firmware=@firmware.bin"
+```
+
+The web interface also supports drag-and-drop firmware upload - simply drag a `.bin` file onto the upload zone.
+
 ## Project Structure
 
 ```
 esp32-bmc/
 ├── CMakeLists.txt           # Project CMake configuration
+├── partitions.csv           # Partition table for OTA
 ├── sdkconfig.defaults       # Default SDK configuration
 ├── .clang-format            # Code formatter configuration
 ├── main/
@@ -190,6 +218,7 @@ esp32-bmc/
 │   ├── uart_handler.c/h     # UART serial communication
 │   ├── ethernet_manager.c/h # W5500 Ethernet setup
 │   ├── web_server.c/h       # HTTP server and routes
+│   ├── ota_handler.c/h      # OTA update handling
 │   └── html/
 │       └── index.html       # Web interface
 └── README.md