Radiation refactor (#22158)

# Summary

This PR refactors radiation values and cleans up custom radiation values
without a definition.
This also fixes #22155.

## Changes

- Update ARMOR_RAD_STRONG 75 -> 70, now fits RAD_LEVEL_VERY_HIGH.
- Update radiation level defines:
  - NONE         = 0
  - VERY_LOW     = 1 (old LOW)
  - LOW          = 10
  - MODERATE     = 25
  - HIGH         = 40
  - VERY_HIGH    = 70 (old value was 100)
  - EXTREME      = 100
  - CATASTROPHIC = 120
- Update a couple of rad values to their respective define name (with
minor implicit balancing).
- Remove the super awkward/LRP hairloss with high radiation exposure.

code/modules/mob/living/carbon/human/life.dm

@@ -235,12 +235,6 @@
 					Weaken(3)
 					if(!lying)
 						emote("collapse")
-				if(prob(5) && prob(100 * RADIATION_SPEED_COEFFICIENT) && species.name == SPECIES_HUMAN) //apes go bald
-					if((h_style != "Bald" || f_style != "Shaved" ))
-						to_chat(src, SPAN_WARNING("Your hair falls out."))
-						h_style = "Bald"
-						f_style = "Shaved"
-						update_hair()
 
 			if (total_radiation > 75)
 				src.apply_radiation(-1 * RADIATION_SPEED_COEFFICIENT)

code/modules/mob/living/carbon/human/species/station/golem.dm

@@ -762,9 +762,7 @@ GLOBAL_LIST_INIT(golem_types, list(
 	..()
 
 /datum/species/golem/uranium/handle_environment_special(var/mob/living/carbon/human/H)
-	if(prob(25))
-		for(var/mob/living/L in view(7, H))
-			L.apply_damage(20, DAMAGE_RADIATION, damage_flags = DAMAGE_FLAG_DISPERSED)
+	SSradiation.radiate(src, RAD_LEVEL_LOW)
 
 /datum/species/golem/homunculus
 	name = SPECIES_GOLEM_MEAT