Ethernet/Bluetooth link status and activity sensors and leds

**Describe the problem you have/What new integration you would like**

Afaik there is no sensor providing info about ethernet link speed and activity. I would like to have option to add sensor informing about ethernet link speed and one more sensor for ethernet activity (idle or busy/active) and one for Bluetooth activity if possible. Bluetooth activity led like the one on RJ45 jack.

**Please describe your use case for this integration and alternatives you've tried:**

Just for information or automation.

**Additional context**

The issue names no implementation files, tests, or entry points. First determine which ESPHome hardware targets and existing sensor or LED integrations could expose Ethernet link speed, Ethernet activity, and Bluetooth activity; done would require a defined scope and observable behavior for the requested sensors and LED.

Written by the indexing model from the issue text.