feat: add W5500 SPI Ethernet support

[Spokplacenta]

Summary

• Integration of W5500 Ethernet controller via SPI for boards like Waveshare ESP32-S3 POE
• Configuration of SPI pins (MOSI, MISO, SCLK, CS, INT, RST) through the web interface
• Direct use of ESP-IDF APIs for W5500 since the Arduino ETH class does not natively support this controller
• Manual DHCP and DNS management for W5500
• Added board presets in the interface (Waveshare ESP32-S3 POE, etc.)

Technical details

The W5500 is an SPI Ethernet controller that is not natively supported by the Arduino ESP32 ETH class. This PR implements:

1. ESP-IDF initialization: Direct use of esp_eth_* APIs to configure the SPI bus and W5500 driver
2. Polling mode: Periodic check of link status and IP address (ESP-IDF event handlers conflict with Arduino)
3. ETH call protection: Methods like ETH.linkSpeed(), ETH.fullDuplex(), etc. are protected to avoid crashes when W5500 is used
4. DNS configuration: DNS is manually configured after obtaining IP via DHCP
5. Skip GitHub OTA: Automatic update check is disabled for W5500 (HTTPClient has issues without WiFi event groups)

Tested boards

• Waveshare ESP32-S3 W5500 POE (pins: MOSI=11, MISO=12, SCLK=13, CS=14, INT=10, RST=9)

Known limitations

• Automatic OTA check from GitHub is disabled for W5500 (to be investigated)
• Manual OTA updates from the web interface have not been tested

Test plan

• W5500 Ethernet connection working
• IP obtained via DHCP
• Web interface accessible via Ethernet
• No crash after several minutes