fix(spells): correct the burning hands damage

PF1e (SRD spells/burning-hands.md): "1d4 points of fire damage per caster level (maximum 5d4)" — the JSON encoded 1d4+1, a flat bonus the spell never grants. Base is now 1d4. Per-caster-level scaling and the 15-ft. cone are not modeled by the engine (no CL-scaled dice, no cone template); documented in README rather than built.

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

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

data/spells/burning_hands.json

@@ -9,10 +9,10 @@
   "effects": [
     {
       "type": "damage",
-      "formula": "1d4+1",
+      "formula": "1d4",
       "types": ["fire"],
       "half_on_save": true
     }
   ],
-  "description": "A cone of searing flame shoots from your fingertips, dealing 1d4+1 points of fire damage per caster level (max 5d4+5). Reflex save for half."
+  "description": "SRD spells/burning-hands.md: 1d4 points of fire damage per caster level (maximum 5d4) in a 15-ft. cone; Reflex half. The engine has no caster-level damage scaling (fixed 1d4) and no cone template (single-target damage with Reflex for half)."
 }