Add weapon data

public/data/weapons/surtr-muspellsverd.json

@@ -0,0 +1,21 @@
+{
+  "id": "surtr-muspellsverd",
+  "name": "Surtr Muspellsverd",
+  "atk": 393,
+  "crt": 43,
+  "rarity": 6,
+  "skills": [
+    {
+      "name": "Eldr of Ragnarok",
+      "description": "[SP: 0][CD: 25s] Consume 50% HP, ignite enemies to deal 20.0% ATK of Fire DMG per 0.5s, and create a shield that can absorb damage equal to 80% of max base HP (5000 max). Shield lasts for 12s, during which: Blood Rose's Ultimate costs no HP; Vermilion Knight: Eclipse’s Ultimate restores 8.0 SP and her Charged ATK and Ultimate deal 30.0% bonus Fire DMG. Weapon active unusable below 20% HP."
+    },
+    {
+      "name": "Rivener of an Era",
+      "description": "When Ultimate or burst mode attacks hit, wielder deals 12% bonus Fire DMG for 13.0s. CD: 1s. 4 stacks max (subsequent procs reset the duration)."
+    },
+    {
+      "name": "Rekindled Fire",
+      "description": "Wielder gains 20% SP recovery, 20% Attack Speed, and 30% Total DMG."
+    }
+  ]
+}