More complete responses for FIDE API requests

As there is currently no official API for FIDE information, it would be extremely useful to be able to retrieve all the fields in the players' list with the lichess API.

The API already returns:

• STD/SRTNG - Standard rating
• RPD/RRTNG - Rapid rating
• BLZ/BRTNG - Blitz rating
• B-day/BORN - year of birth of a player
• ID NUMBER - identification number of a player within FIDE database
• NAME - name of a player
• TIT/TITL - title of a player (g - Grand Master, wg - Woman Grand Master, m - Interntional Master, wm - Woman International Master, f - FIDE Master, wf - Woman FIDE Master, c - Candidate Master, wc - Woman Candidate Master)
• FED - Federation of a player
• FLAG - flag of inactivity (I - inactive, WI - woman inactive, w - woman)

It would also be useful for the API to return the remaining fields:

• SGM - number of STANDARD rated games in given period
• RGM - number of RAPID rated games in given period
• BGM - number of BLITZ rating games in given period
• SK - STANDARD rating K factor
• RK - RAPID rating K factor
• BK - BLITZ rating K factor
• OTIT - Other titles of a player which may include (IA - International Arbiter, FA - FIDE Arbiter, NA - National Arbiter, IO - International Organizer, FT - FIDE Trainer, FST - FIDE Senior Trainer, DI - Developmental Instructor, NI - National Instructor)
• SEX - sex of a player (M - male, F - female)

Start by reviewing the existing lichess API response for the FIDE players' list and the repository's documentation and examples. Identify how the requested SGM, RGM, BGM, SK, RK, BK, OTIT, and SEX fields are represented, then verify that the endpoint response includes them.