[Contribution Idea] "Keep Original Type Themes" for trainers

[foxoftheasterisk]

Is your idea a new setting, a change to an existing setting, or something else? Please describe clearly: This is a new setting that appears in the trainers main dropdown. It works as follows: If every Pokemon a trainer originally had is of the same type, the Pokemon chosen will also all be that type. (Always triggers if the trainer had only one Pokemon.) If all the Pokemon share two types, the primary type of the first Pokemon in the party is chosen - unless it's Normal, in which case the secondary is chosen instead.

What problem would your contribution solve? Please describe: Allows players to randomize trainer Pokemon without losing knowledge such as, e.g., "Fishermen have all water types" and "Bug catchers have all bugs". Also, allows playing with Gym leaders on their original types.

Additional context: This feature is already completed, actually.

I understand that I am expected to implement this change myself in the randomizer's codebase: [X]