adding abilities, created skill tree template and unlock mechanics

api/app/data/abilities/vanish.yaml

@@ -0,0 +1,25 @@
+# Vanish - Assassin Shadow Dancer ability
+# Stealth for 2 turns
+
+ability_id: "vanish"
+name: "Vanish"
+description: "Disappear into the shadows, becoming invisible for 2 turns and dropping threat"
+ability_type: "skill"
+base_power: 0
+damage_type: null
+scaling_stat: "dexterity"
+scaling_factor: 0.3
+mana_cost: 25
+cooldown: 5
+is_aoe: false
+target_count: 1
+effects_applied:
+  - effect_id: "stealth"
+    name: "Stealthed"
+    effect_type: "buff"
+    duration: 2
+    power: 100
+    stat_affected: null
+    stacks: 1
+    max_stacks: 1
+    source: "vanish"