The Arduino IDE requires the use of a single true tab separator between the keyword name and identifier. When spaces are used rather than a true tab, the keyword is not highlighted.

Reference:
https://github.com/arduino/Arduino/wiki/Arduino-IDE-1.5:-Library-specification#keywords

Use correct field separator in keywords.txt

From the Arduino Sketch Specification:
https://arduino.github.io/arduino-cli/dev/sketch-specification/#sketch-folders-and-files

> The sketch root folder name and code file names must start with a basic letter (A-Z or a-z) or number (0-9), followed
> by basic letters, numbers, underscores (_), dots (.) and dashes (-).

Use specification compliant sketch file name

Doc correction and clarified SoC core requirement.