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

data/spells/spear_of_purity.json

@@ -5,6 +5,7 @@
   "range": "close",
   "save": "will",
   "base_dc": 10,
+  "cast_time": "standard",
   "effects": [],
   "description": "A spear of good energy (ranged touch attack): evil creatures take 1d8 per two caster levels (max 5d8); evil outsiders take 1d6 per caster level (max 10d6) and are blinded 1 round. A successful Will save halves the damage and negates the blind. Half damage to neutral creatures, no effect on good ones. No combat effect encoded: the engine has no alignment, so the alignment-gated damage cannot be represented."
 }