Add Animations feature + fix own-pet tooltip false positive

Animations (all optional, default on, per-effect toggles):
- New Options -> Animations tab with master switch + per-effect checkboxes
- Embed PizzaSauce animation library (api/PizzaSauce.lua)
- fx-celebrate: firework + banner when a pet learns a new ability/rank,
  triggered from core-scan-beasttraining pet-learn hook
- Hunter's Book: slide + fade on open, results list fade on tab switch
- Options window: slide + fade on open
- All new user-facing strings keyed (ANIM_* namespace)

Fixes:
- Tooltip #19: own-pet lines (mood/loyalty/happiness/XP) no longer
  misfire on party members / targets. Removed the fragile title-name
  fallback in MTH_TT_IsTooltipOnOwnPet; ownership now requires positive
  unit identity.

Temp (remove before release): /mth fx and /mth fxdebug diagnostics.

api/core-scan-beasttraining.lua

@@ -432,6 +432,9 @@ local function MTH_PT_ProcessLearnSystemMessage(rawMessage)
 		if changed then
 			MTH_PT_ApplyScan("learn-msg")
 		end
+		if changed and type(MTH_CelebratePetAbility) == "function" then
+			MTH_CelebratePetAbility(label)
+		end
 		if type(MTH_PSP_RequestScan) == "function" then
 			MTH_PSP_RequestScan("train-learn-msg")
 		end