fix(rules): set the slumber hex duration to the witch level

PF1e (APG Slumber): the target "remains asleep for a number of rounds equal to the witch's level" (Will negates). _hex_slumber hardcoded 1 round; it now uses the caster's level. The RAW clause that the hex ends when the target takes damage is not modeled (no wake-on-damage hook in the engine) — documented in README. Two behavioral tests pin the failed-save duration (= level) and the saved case.

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

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

src/pf1e_simulator/combat.py

@@ -4783,7 +4783,10 @@ class CombatEngine:
     def _hex_slumber(
         self, state: CombatantState, target: CombatantState, hex_dc: int
     ) -> None:
-        """Slumber: asleep/disabled if Will fails."""
+        """Slumber (APG): the target remains asleep for a number of rounds
+        equal to the witch's level; a successful Will save negates.
+        Simplification documented in README: the RAW ending of the hex when
+        the target takes damage is not modeled (no wake-on-damage hook)."""
         save_result = self.resolve_save(target, "will", hex_dc)
         if save_result.success:
             self._log(
@@ -4791,16 +4794,17 @@ class CombatEngine:
                 f"{target.combatant.id} -> SAVED"
             )
             return
+        rounds = state.combatant.level
         target.active_conditions.append(
             ActiveCondition(
                 condition=CONDITIONS_BY_NAME["asleep"],
-                rounds_left=1,
+                rounds_left=rounds,
                 source=f"hex: slumber by {state.combatant.id}",
             )
         )
         self._log(
             f"round {self._current_round} {state.combatant.id}: slumber on "
-            f"{target.combatant.id} -> asleep (1r)"
+            f"{target.combatant.id} -> asleep ({rounds}r)"
         )
 
     def _hex_cackle(self, state: CombatantState, target: CombatantState) -> None: