[script][combat-trainer] Updates for focus_threshold

[mdr55]

updates

1. The hard minimum for focus_threshold may be too conservative. A value of ~4 may be workable for a weapon tert. For other skillset placements focus_threshold may need to be higher to account for drain whilst stuck on a weapon going for 34/34 (so you don't end up with 0 ms on a skill with no ability to correct until the 34 is done). Setting the minimum to say > 1 gives the player freedom to set what is needed for their char and specific circumstances.
2. Conditional CT break bug fix (if focus_threshold was activated + the bottom of the hysterisis band was reached). Rookie mistake :(

[mdr55]

ready for review. #2 is conditionally breaking for users of feature