Add trigger functionality to Focused Ballista Support

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Is your feature request related to a problem?

It would be nice if Focused Ballista Support could "trigger" supported ballista totem skills, limiting their attack rate the same way that Asenath's Chant or similar effects limit the trigger rate of spells based on the attack speed of the triggering skill.

Describe the solution you'd like

Adding Focused Ballista Support to a skill group should cause ballista totem skills in that group to have their attack rate limited to the attack rate of a "triggering skill" that is used by the player, subject to the same effects as all other triggers in PoB (missed trigger intervals reducing the trigger rate, warning when no trigger is found, etc.). This would of course use the totem's attack speed as the limit to the trigger rate, as opposed to other triggers that use an internal cooldown.

Describe alternatives you've considered

Currently, to calculate true DPS from ballista skills supported by Focused Ballista, you have to do all of the trigger rate calculations and comparisons by hand.

Additional context

No response

Start by locating the Focused Ballista Support handling and the existing trigger calculations in the Lua codebase. Compare how current triggers handle attack rate limits, missed intervals, and missing triggering skills. Done means supported ballista totems use the triggering skill's rate and expose the same warnings and rate calculations without manual comparison.