- Use a global pointer for the current sanitized command
- Pre-sanitize the current command to bypass `N` and nullify `*`,
removing the need for handlers to bypass, ignore, or nullify these
parts, and reducing overhead for `code_seen`, etc.
- Pre-skip leading whitespace.
- Only look for G, M, T codes at the start of the command.
- Verify that G, M, T codes are followed by command codes.

- For better encapsulation add inlines for each prepare_move type
- Move controllerFan vars inside the function as statics
- Some formatting cleanup
- Rename `ClearToSend` as `ok_to_send`

- create sled pin definition
- G28 Works with sled

- Make thermal protection for all hotends and/or bed into simple
switches
- Now enable `WATCH_TEMP_PERIOD` when `THERMAL_PROTECTION_HOTENDS` is
enabled
- Move detailed thermal parameters to `Configuration_adv.h`
- Add sanity checks to warn about old configurations
- Change `WATCH_TEMP_PERIOD` to seconds instead of milliseconds

ok N(linenumber) P(bufferremaining)
the host can use this to send the data much faster.

Some pseudo code:
If (bufferremaining > 0)  send command
## as long there is free buffer send command

Also
if (linenumber > lastsend - bufferremaining) send command
## as long last linenumber received is bigger than lastsend (host) - last bufferremaining received

Persistent homing message.
Message was declared as an alert, therefore it was persistent.
Updated to message.

This reverts the changes done to the error message for line number mismatches done in commit d43cc2dd5f

Servo.cpp and Servo.h were changed to lowercase in Makefile but not their actual filenames.

- Also move audio feedback into the command
- Added shorthand for `lcd_buzz` availability