Summoning considerations for linked (e.g. unique) actors.

[trioderegion]

• Unlinked actor summoning remains the same.
• Linked actor summoning:
  • additionally considers the dnd5e.summon.origin flag, which associates a given summoned actor instance with a specific item on a specific actor.
  • actor/item/effect changes are applied to the actor via standard CRUD operations instead of inserting directly into the token's delta field.
  • Intended for use with 'permanent' summons/companions.

[trioderegion]

Relevant helpers or similar lookups found in #3545 and could be utilized.

[trioderegion]

Note: I realize after writing this that the primary concern was with the current HP, my comments below are primarily related to updating Max HP. Updating the current+max HP of an unlinked summon makes sense, but for linked, only adjusting the max may be more correct as you point out.

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Regarding the increasing HP for linked summons. It was intentional that the summons received these bonuses, though, admittedly, the HP Bonus formula needs to be more complex to ensure bonuses are not "stacked" erroneously.

This allows permanent summons to be "resummoned" to re-adjust any summoner derived-stats. When scenes are switched or otherwise another token of that summon is needed, dragging from the sidebar would be the general approach -- though, as mentioned, clever hp bonuses using the summon's current hit dice count can overcome this.

The other bonuses like AC and damage would need similar user-side considerations depending on exactly how said permanent summon works.

I'm wondering if a tooltip or additional hint text would be helpful to explain this as I do think there is value to "additively" modifying a linked summon -- though I do appreciate how the nuances of such for the user may be murky.

[trioderegion]

Force push to clean up unneeded fast-forward merge from 3.2.x

[trioderegion]

Will look into max HP modifications for linked summons via AEs to avoid unintended "stacking" from repeated summoning.