feat: Remove banned mana types (life, blood, wood, mental, force) and lifesteal

- Remove life, blood, wood, mental, force mana types from ELEMENTS
- Remove all spells using banned mana types
- Remove lifesteal from all remaining spells and effects
- Update guardian perks to remove lifesteal mentions
- Remove research skills for banned spell types
- Update tests to reflect new element structure
- Add BANNED CONTENT section to AGENTS.md (lifesteal/healing ban)
- Add mana types overview to README.md and AGENTS.md
- All 44 tests pass, lint clean

README.md

@@ -20,9 +20,60 @@ An incremental/idle game about climbing a magical spire, mastering skills, and u
 
 ### Mana Gathering & Management
 - Click-based mana collection with automatic regeneration
-- Elemental mana system with five elements (Fire, Water, Earth, Air, Void)
+- Elemental mana system with multiple elements
 - Mana conversion between raw and elemental forms
 - Meditation system for boosted regeneration
+- Compound mana types created from base elements
+- Exotic mana types for ultimate power
+
+---
+
+## 🔮 Mana Types
+
+Mana is the core resource of Mana Loop. There are four categories of mana types:
+
+### Base Mana Types (7)
+| Element | Symbol | Color | Theme |
+|---------|--------|-------|-------|
+| Fire | 🔥 | #FF6B35 | Destruction, burn damage |
+| Water | 💧 | #4ECDC4 | Flow, freeze effects |
+| Air | 🌬️ | #00D4FF | Speed, wind damage |
+| Earth | ⛰️ | #F4A261 | Stability, armor pierce |
+| Light | ☀️ | #FFD700 | Radiance, holy damage |
+| Dark | 🌑 | #9B59B6 | Shadows, void damage |
+| Death | 💀 | #778CA3 | Decay, rot damage |
+
+### Utility Mana Types (1)
+| Element | Symbol | Color | Theme |
+|---------|--------|-------|-------|
+| Transference | 🔗 | #1ABC9C | Mana transfer, Enchanter attunement |
+
+### Compound Mana Types (3)
+Created by combining two base elements:
+| Element | Recipe | Theme |
+|---------|--------|-------|
+| Metal | Fire + Earth | Armor piercing, forged weapons |
+| Sand | Earth + Water | AOE damage, desert winds |
+| Lightning | Fire + Air | Fast damage, armor pierce, chain effects |
+
+### Exotic Mana Types (3)
+Created from advanced recipes:
+| Element | Recipe | Theme |
+|---------|--------|-------|
+| Crystal | Sand + Sand + Light | Prismatic, high damage |
+| Stellar | Fire + Fire + Light | Cosmic, ultimate fire/light |
+| Void | Dark + Dark + Death | Oblivion, ultimate dark/death |
+
+### Mana Type Hierarchy
+```
+Base Elements (7)
+       ↓
+Compound (3)    Utility (1)
+       ↓
+Exotic (3)
+```
+
+---
 
 ### Skill Progression with Tier Evolution
 - 20+ skills across multiple categories (mana, combat, enchanting, familiar)