feat(runner): wire spell registry in CLI and Monte Carlo

tests/test_runner_spells.py

@@ -0,0 +1,66 @@
+"""Wiring tests: the Monte Carlo runner loads the real spell registry and
+spellcasting PCs cast against ``data/spells/``.
+
+The engine's ``spell_registry`` defaults to ``{}`` for retro-compat with pure
+unit tests; the runner must therefore load the registry from ``SPELLS_DIR`` and
+pass it into every ``CombatEngine`` so a caster PC actually produces
+``cast_spell`` actions in Monte Carlo.
+"""
+
+from __future__ import annotations
+
+from pathlib import Path
+
+from pf1e_simulator.combat import CombatEngine
+from pf1e_simulator.grid import Grid
+from pf1e_simulator.loaders import load_combatant
+from pf1e_simulator.map import load_map
+from pf1e_simulator.rng import SeededRng
+from pf1e_simulator.runner import EncounterSpec, Side, build_states
+from pf1e_simulator.spells import SPELLS_DIR, load_spell_registry
+
+ROOT = Path(__file__).resolve().parents[1]
+MAP = ROOT / "data" / "maps" / "sample_arena.yaml"
+ONI = ROOT / "data" / "pcs" / "oni.json"
+GOBLIN = ROOT / "data" / "monsters" / "goblin.json"
+
+_NUM_SPELLS = 11
+
+
+def test_runner_loads_realtime_spell_registry() -> None:
+    """The runner's registry source holds all 11 real spells from data/spells/."""
+    registry = load_spell_registry(SPELLS_DIR)
+    assert len(registry) == _NUM_SPELLS
+
+
+def test_monte_carlo_caster_pc_casts_spell() -> None:
+    """oni (cleric) casts against data/spells/ once it drops below 50% HP.
+
+    oni's known spells overlap the registry's heal spells (Cure Light/Moderate
+    Wounds); with enough damage taken it heals via cast_spell. The Monte Carlo
+    loop mirrors run_encounter: build fresh states and one CombatEngine per run
+    with the registry from SPELLS_DIR.
+    """
+    spec = EncounterSpec(
+        map=load_map(MAP),
+        round_cap=100,
+        sides=(
+            Side(name="players", combatants=(load_combatant(ONI),), zone="A"),
+            Side(name="monsters", combatants=(load_combatant(GOBLIN),) * 4, zone="B"),
+        ),
+    )
+    registry = load_spell_registry(SPELLS_DIR)
+    grid = Grid.from_spec(spec.map)
+    casts = 0
+    for i in range(100):
+        states = build_states(spec)
+        rng = SeededRng(7 + i)
+        result = CombatEngine(
+            rng, grid, states, round_cap=spec.round_cap, spell_registry=registry
+        ).run()
+        casts += sum(
+            1
+            for line in result.transcript
+            if " vs " in line and "cast " in line
+        )
+    assert casts > 0