Unique npc ids, allow interacting with npcs that are not in reality bubble

[Ramza13]

Summary

None

Purpose of change

Part of #57419
Allow eocs to interact with npcs outside of reality bubble.

Describe the solution

Added new unique_id field to npc that can be optionally set via mapgen. Change u_run_npc_eocs to use this and allow it to be used at any distance.

Describe alternatives you've considered

Testing

Used this json

{
    "type": "effect_on_condition",
    "id": "test",
    "effect": [ { "u_run_npc_eocs": [
{
  "id":"test2",
  "effect":{ "arithmetic": [ { "u_val": "thirst" }, "++" ] }
}
    ], "unique_ids": ["test"] } ]
  },

after changing the line in refugee_center.json to this

{ "class": "free_merchants_merchant", "x": 71, "y": 0, "unique_id":"test" },

Additional context