perf: change frequency of cached weapon value update

[OrenAudeles]

Summary

SUMMARY: Performance "Change frequency of NPC cached weapon value update"

Purpose of change

One of the hotspots of NPC update is regeneration of the AI cache. One part in particular, ai_cache.my_weapon_value = npc_ai::wielded_value( *this );, is very slow to process taking around 1/3 of the total singular NPC update time. Looking deeper at where ai_cache.my_weapon_value is used we see a single access location in npc::character_danger which is itself only called from npc::evaluate_enemy when the passed parameter is an NPC or Player.

Because ai_cache.my_weapon_value is not the only consideration when evaluating perceived danger I don't think it will be harmful to the NPC to be a little inaccurate in that consideration by having mildly outdated information.

Describe the solution

Pretty simple. Wrapped the line so that it only is evaluated once per minute instead of every turn. 1/60th the executions => 1/60th the execution time at the expense of a little information inaccuracy.

Testing

Started a new world, new character in the refugee center as in #3277 and repeatedly wait for 1 hour, timing with phone timer. Times are in seconds to wait 1 hour in the refugee center with 37 NPCs and 19 Monsters in the reality bubble.

Mode	Run 1	Run 2	Run 3	Run 4	Run 5	Average
Pre #3277	38.87	38.92	38.63	39.36	38.86	38.928
#3277	31.94	32.40	32.50	32.05	31.75	32.128
This PR	23.51	23.20	23.04	23.12	23.74	23.322

Average time saved per waited hour relative to PR-3277 : 8.806s (27.41% better)
Average time saved per waited hour relative to pre-3277 : 15.606s (40.09% better)

[scarf005]

impressive.

test method: waited 6h at refugee center with debug sight and timers enabled