chore(scanner): formatting improvements

[ObserverOfTime]

• Add space after type casts and sizeof
• RAW_STRING_DELIMITER_MAX -> MAX_DELIMITER_LENGTH (more intuitive?)
• Remove the scan function and inline its contents
• Replace _Static_assert with static_assert
  • Provided by assert.h since C11
  • Manually defined as assert otherwise
• Some minor nitpicks

[amaanq]

most of it looks good though I do prefer casts without a space in between (and with parenthesis) 😅

[ObserverOfTime]

Casts or sizeof?

[amaanq]

both, sorry for not being clear