feat(backend): Integrate Derived Stats into combat, loot, and crafting mechanics

api/database.py

@@ -308,6 +308,16 @@ player_statistics = Table(
 )
 
 
+character_perks = Table(
+    "character_perks",
+    metadata,
+    Column("id", Integer, primary_key=True, autoincrement=True),
+    Column("character_id", Integer, ForeignKey("characters.id", ondelete="CASCADE"), nullable=False),
+    Column("perk_id", String(50), nullable=False),
+    Column("acquired_at", Float, nullable=False),
+    UniqueConstraint("character_id", "perk_id", name="uix_character_perk")
+)
+
 # ========================================================================
 # QUESTS AND TRADE TABLES
 # ========================================================================
@@ -2937,3 +2947,47 @@ async def acknowledge_pvp_combat(combat_id: int, player_id: int) -> bool:
             
         await session.commit()
         return True
+
+
+# ========================================================================
+# CHARACTER PERKS
+# ========================================================================
+
+async def get_character_perks(character_id: int) -> list:
+    """Get all perks owned by a character."""
+    async with DatabaseSession() as session:
+        stmt = select(character_perks).where(
+            character_perks.c.character_id == character_id
+        )
+        result = await session.execute(stmt)
+        return [dict(row._mapping) for row in result.fetchall()]
+
+
+async def add_character_perk(character_id: int, perk_id: str) -> bool:
+    """Add a perk to a character. Returns False if already owned."""
+    import time
+    async with DatabaseSession() as session:
+        try:
+            stmt = insert(character_perks).values(
+                character_id=character_id,
+                perk_id=perk_id,
+                acquired_at=time.time()
+            )
+            await session.execute(stmt)
+            await session.commit()
+            return True
+        except Exception:
+            return False
+
+
+async def remove_character_perk(character_id: int, perk_id: str) -> bool:
+    """Remove a perk from a character."""
+    async with DatabaseSession() as session:
+        stmt = delete(character_perks).where(
+            character_perks.c.character_id == character_id,
+            character_perks.c.perk_id == perk_id
+        )
+        result = await session.execute(stmt)
+        await session.commit()
+        return result.rowcount > 0
+