fix(rules): require a ranged touch attack for ray spells

PF1e CRB (Magic - Ranged Touch Attacks): spells delivered by ray require a
ranged touch attack (BAB + Dex vs touch AC, no range increment) to hit a
hostile target; a miss wastes the slot. SpellSpec gains requires_ranged_touch,
set on the 8 SRD-confirmed rays (Ray of Frost, Ray of Enfeeblement, Scorching
Ray, Acid Arrow, Acid Splash, Disrupt Undead, Shard of Chaos, Spear of Purity).
Magic Missile and area spells are unaffected. Simplification (documented): no
size modifier / Weapon Finesse on the roll.

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>

data/spells/acid_arrow.json

@@ -5,6 +5,7 @@
   "range": "medium",
   "save": "none",
   "base_dc": 10,
+  "requires_ranged_touch": true,
   "cast_time": "standard",
   "effects": [
     {