Add list of obligatory flags to MA techs

[Venera3]

Summary

None

Purpose of change

Gate certain melee techs behind having all of an arbitrary list of character flags to facilitate e.g. multi-arm strikes being forbidden when any one arm is disabled / overencumbered.

Describe the solution

Add required_char_flags_all, defining a list of character flags the character needs to trigger a given tech.

Describe alternatives you've considered

Make it a pair of [ "FLAG", count], but this allows requiring a combination of different flags.

Testing

Used the WIP 4 Tentacles mutation adding 4 tentacles, each with an armed/unarmed/single tech and the conditional flags 4TENTACLE_1 through _4. The unarmed attack requires all four flags, the others are satisfied by any one. The unarmed tech triggered as expected with all four flags and stopped triggering when one of the arms got damaged below the health limit, the other techs triggered until no tentacles were left.