Fixes education age restriction and max skill level in educated skills (#22645)

The education age restriction now applies to tajara and unathi as well.
The max skill level was supposed to be unlocked in educated skills, but
was being accidentally locked to only the skill level the education
gave. This meant someone uneducated could sometimes get even higher
skill than an educated person, by spending skill points.
The three combat skill ranks were reduced to trained level as their max.
It was not possible for players to get higher before, and 3 was already
the baseline. If a professional is ever implemented for antags or
similar, it can be set back again then.
Doctor of Pharmacy was reduced to only need 25 years old, due to both
the description and that the pharmacist job has that age requirement
too.

fixes https://github.com/Aurorastation/Aurora.3/issues/22376
fixes https://github.com/Aurorastation/Aurora.3/issues/22286
fixes https://github.com/Aurorastation/Aurora.3/issues/22232 kinda. It
was already fixed, but more fixing on restrictions also reported on it.
fixes https://github.com/Aurorastation/Aurora.3/issues/22610

code/datums/skills/_skills.dm

@@ -62,7 +62,7 @@
 
 	// Otherwise, we need to check the education...
 	if(type in education.skills)
-		return education.skills[type]
+		return maximum_level
 
 
 	return uneducated_skill_cap

code/datums/skills/combat/combat.dm

@@ -16,7 +16,7 @@
 	name = "Unarmed Combat"
 	description = "Unarmed combat represents your training in hand-to-hand combat, or without a weapon. It also influences your ability to resist actions like disarms or martial arts. " \
 		+ "Higher ranks in Unarmed Combat provide bonuses when attacking with your fists, as well as bonuses to defending against others unarmed attacks and disarms."
-	maximum_level = SKILL_LEVEL_PROFESSIONAL
+	maximum_level = SKILL_LEVEL_TRAINED
 	skill_level_descriptions = alist(
 		SKILL_LEVEL_UNFAMILIAR = "You have rarely, if ever, fought someone in your life.<br>" \
 			+ " - You are more likely to miss when attempting to punch anywhere not the torso.<br>" \
@@ -43,7 +43,7 @@
 /singleton/skill/armed_combat
 	name = "Armed Combat"
 	description = "Armed Combat influences your effectiveness when fighting with any melee weapon. Having low ranks in this skill slightly decreases damage dealt with melee weapons, while higher ranks can slightly increase it."
-	maximum_level = SKILL_LEVEL_PROFESSIONAL
+	maximum_level = SKILL_LEVEL_TRAINED
 	category = /singleton/skill_category/combat
 	subcategory = SKILL_SUBCATEGORY_MELEE
 	component_type = ARMED_COMBAT_SKILL_COMPONENT
@@ -51,7 +51,7 @@
 /singleton/skill/firearms
 	name = "Firearms"
 	description = "Firearms represents your training in using all forms of ranged weapons. Having a high rank in in this skill provides bonuses to accuracy when shooting."
-	maximum_level = SKILL_LEVEL_PROFESSIONAL
+	maximum_level = SKILL_LEVEL_TRAINED
 	category = /singleton/skill_category/combat
 	subcategory = SKILL_SUBCATEGORY_RANGED
 	required = TRUE