Better OpenAI API support, Sapphire image gen options

Under "OpenAI/Oobabooga API" option, added the option to specify an API key and a model, if the server requires it. This means you can use it for OpenRouter, OpenAI, and other services which use the OpenAI API format and require an API key. For services or local programs not requiring these fields, e.g. Oobabooga or LMStudio, you should leave these fields blank.

Added two additional styles for Sapphire Image Gen: Anime, and Vibrant.

Fixed a null pointer error which sometimes occurred during the "location mentioned" event check.