Accept custom protocols in RF-Switch based remote transmitter

**Describe the problem you have/What new integration you would like**
I want to send a RF signal to open my garage door. I made this work with RF-Switch. Now I would like the RF-Switch based remote transmitter to also accept custom protocols.

**Please describe your use case for this integration and alternatives you've tried:**
See above. I already implemented it outside of ESPHome but now wanna use ESPHome instead of some homemade solution.

**Additional context**
None

The request concerns the RF-Switch-based remote transmitter and accepting custom protocols for a garage-door signal. Start by locating the transmitter component and its protocol handling; the issue names no files, tests, or entry points, so the required interface and completion criteria need to be established before implementation.

Written by the indexing model from the issue text.