NPCs: fix NPC fleeing and allow NPCs to stop fleeing the player

[mlangsdorf]

Summary

SUMMARY: Bugfixes "NPCs: fix NPC fleeing and allow NPCs to stop fleeing the player"

Purpose of change

Fix an issue where NPCs fleeing from the player could melee attack the player at a great distance.

Fix an issue where an NPC, once they became scared of the player, became scared of the player forever.

Fix a warning message regarding the snippet and warning messages when setting NPC attitudes in the debug menu.

Describe the solution

Due to a bug in the NPC flight code, NPCs that were fleeing from the player could punch him at a distance. Change the logic for calling good_escape_direction from npc_has_effect( effect_npc_run_away) to npc_action == npc_flee. Now NPCs that are fleeing move_to a tile away from the NPC, instead of trying to move to the PC and being unable and punching him instead.

NPCs get a new attitude, NPCATT_FLEE_TEMP, whenever they would get NPCATT_FLEE. When an NPC's attitude is set to NPCATT_FLEE_TEMP, they also get a 24 hour effect "npc_flee_player." When the NPC AI starts its routine each turn, NPCATT_FLEE is turned to NPCATT_FLEE_TEMP and then if the NPC has NPCATT_FLEE_TEMP but not "npc_flee_player" they revert to NPCATT_NULL.

Change the color of fleeing NPCs to light_red to distinguish them from actual hostiles.

isn't a valid snippet, so replace it in talk_tags.json.

Give descriptions to the legacy NPC attitudes so that the new debug menu option to set an NPC attitude stops spewing error messages.

Describe alternatives you've considered

This could technically be 3 PRs but only the second commit is large enough to break out on its own.

[kevingranade]

This pull request has been mentioned on Cataclysm: Dark Days Ahead. There might be relevant details there:

https://discourse.cataclysmdda.org/t/npcs-shooting-punches/19426/7