fix(spells): backfill casting times for all imported spells

data/spells/hex_vulnerability.json

@@ -5,6 +5,7 @@
   "range": "close",
   "save": "will",
   "base_dc": 10,
+  "cast_time": "standard",
   "effects": [],
   "description": "The target becomes susceptible to a repeat use of your harmful hexes for 1 round/level, bypassing the once-per-day targeting limit. Will negates. No combat effect: the hex-reuse permission is outside the engine's model, so the spell has no mechanical effects here."
 }