fw-rust: Refactor everything

Remove avr-eeprom dependency for now and introduce events.

firmware/rust/Cargo.lock

@@ -32,15 +32,6 @@ dependencies = [
  "syn",
 ]
 
-[[package]]
-name = "avr-eeprom"
-version = "0.1.0-dev"
-source = "git+https://git.onders.org/finga/avr-eeprom-rs.git?branch=main#96397b5fbbaaa8531842db301127c1346f6e05f9"
-dependencies = [
- "avr-device",
- "nb 1.0.0",
-]
-
 [[package]]
 name = "avr-hal-generic"
 version = "0.1.0"
@@ -76,7 +67,6 @@ version = "0.1.0-dev"
 dependencies = [
  "atmega-hal",
  "avr-device",
- "avr-eeprom",
  "embedded-hal",
  "nb 1.0.0",
  "panic-halt",