Adds documentation for the `omath::ViewAngles` struct,
clarifying its purpose, common usage patterns,
and the definition of the types of pitch, yaw and roll.
Also, adds short explanations of how to use ViewAngles and what tradeoffs exist
between using raw float types and strongly typed Angle<> types.
Applies a dark theme to the documentation site using the `darkly` theme.
Provides a visually appealing dark mode option.
Configures colors to ensure readability and aesthetic consistency.
