Feature: Archive characters when handling CMSG_CHAR_DELETE instead of outright deleting the row

[bigglesss]

Right now, sending CMSG_CHAR_DELETE from a client will completely remove the character row from the table. Ideally, this should be slightly less aggressive:

• Set a deleted column on the characters table row that prevents it from being sent to clients in SMSG_CHAR_ENUM.
• Allow settings to be configured in a similar way to vmangos, see https://github.com/vmangos/core/blob/440d15c7eded24066076d452b96281ea7a4c8c29/src/mangosd/mangosd.conf.dist.in#L2735

[Victov]

I think the .env and the .env.template could be a fine place for that configuration, no need for a whole new system with another config format.