fix(rules): keep swift and free actions for staggered combatants

PF1e (CRB, Staggered): a staggered creature takes a single move OR standard action but can still take free, swift, and immediate actions. _staggered_filter returned only the first non-full-round action, so a disabled combatant with a queued swift bonus (deed/inspire_courage) lost its standard action. It now keeps every swift and free action plus the first move-or-standard, preserving the full_attack -> single attack downgrade.

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

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

README.md

@@ -339,7 +339,8 @@ Règles modélisées :
 - Invalide (conformance P2, CRB « Effects of Death ») : à `hp = 0`
   exactement, une créature est **invalide** — elle reste active mais
   **staggered** (une action de mouvement OU une action standard par tour, pas
-  d'action à round complet), se déplace à **moitié vitesse**, et achever une
+  d'action à round complet, mais les actions swift, libre et immédiate restent
+  permises — CRB « Staggered »), se déplace à **moitié vitesse**, et achever une
   action non-mouvement (standard ou pénible) lui coûte **1 pv** à la fin de
   cette action (pv → −1, agonie). Simplification documentée : si l'action
   elle-même soigne la créature au-dessus de 0 pv, ce coût n'est pas appliqué.
@@ -857,7 +858,9 @@ Règles modélisées :
   de mouvement (`move`, `5foot_step`, `stand_up`, `drop_prone`) et bloque toute
   attaque, manœuvre **et incantation** (CRB : un nauséeux ne peut ni attaquer,
    ni incanter, ni se concentrer) ; `staggered` restreint à une action
-  simple (pas d'attaque à outrance) ; `cant_move` bloque le déplacement ;
+   simple (une action de mouvement OU standard, pas d'attaque à outrance ni
+   d'action à round complet, mais swift/libre/immédiate conservées) ;
+   `cant_move` bloque le déplacement ;
   `denies_dex_to_ac` (flat-footed, paralysé, aveuglé…) fait perdre le bonus de Dextérité à
   la CA (CA flat-footed) ; `miss_chance` (flou 20 %, déplacement 50 %, invisible
   50 %) impose la

src/pf1e_simulator/combat.py

@@ -6054,19 +6054,40 @@ def _staggered_filter(
     *,
     cast_time: CastTimeResolver = _default_cast_time,
 ) -> tuple[Action, ...]:
-    """Staggered: one move OR one standard action per round, no full-round.
+    """Staggered: one move OR one standard action, plus every swift and free.
 
-    A leading ``full_attack`` (already in range) becomes a single standard
-    ``attack``; anything whose effective slot is full-round (charge,
-    withdraw, run, a full-round/one-round cast, spell_combat) is dropped.
+    PF1e (CRB, Conditions — Staggered): "A staggered creature may take a
+    single move action or standard action each round (but not both, nor can
+    he take full-round actions). A staggered creature can still take free,
+    swift, and immediate actions." So the filter walks the sequence in order
+    and keeps every swift and free action, the FIRST move-or-standard action,
+    and drops full-round actions plus any SECOND move-or-standard. A leading
+    ``full_attack`` (already in range) is downgraded to a single standard
+    ``attack`` that consumes the one move-or-standard slot; a further
+    full-round action (charge, withdraw, run, a full-round/one-round cast,
+    spell_combat) is dropped.
     """
+    kept: list[Action] = []
+    slot_used = False  # the single move-OR-standard slot is spent
     for action in actions:
         if action.kind == "full_attack":
-            return (Action(kind="attack", target_id=action.target_id),)
-        if _effective_slot(action, cast_time) == "full_round":
+            # A full attack is a full-round action; staggered it collapses to
+            # a single standard attack (the kept move-or-standard action).
+            if not slot_used:
+                kept.append(Action(kind="attack", target_id=action.target_id))
+                slot_used = True
             continue
-        return (action,)
-    return ()
+        slot = _effective_slot(action, cast_time)
+        if slot == "full_round":
+            continue
+        if slot in ("standard", "move"):
+            if slot_used:
+                continue
+            kept.append(action)
+            slot_used = True
+        else:  # swift / free — always allowed while staggered (CRB)
+            kept.append(action)
+    return tuple(kept)
 
 
 def _nauseated_filter(actions: tuple[Action, ...]) -> tuple[Action, ...]:

tests/test_conformance_action_economy.py

@@ -33,6 +33,7 @@ from pf1e_simulator.combat import (
     _cast_time_slot,
     _dropped_kinds,
     _dropped_kinds_multiset,
+    _staggered_filter,
     default_policy,
 )
 from pf1e_simulator.conditions import CONDITIONS_BY_NAME
@@ -309,6 +310,46 @@ def test_staggered_after_budget_keeps_single_legal_action() -> None:
     assert ("charge", "downgraded:staggered") in reasons
 
 
+# ── (d2) the staggered filter keeps swift + free, one move-OR-standard ─────────
+
+
+def test_staggered_filter_keeps_swift_and_free_actions() -> None:
+    # PF1e (CRB, Staggered): a single move OR standard, but free/swift/immediate
+    # actions are still allowed. The policy's swift deed must not be dropped.
+    assert _staggered_filter((_foe("deed"), _foe("attack"))) == (
+        _foe("deed"),
+        _foe("attack"),
+    )
+    # A swift taken AFTER the standard is likewise kept.
+    assert _staggered_filter((_foe("attack"), _foe("deed"))) == (
+        _foe("attack"),
+        _foe("deed"),
+    )
+    # A free 5-foot step survives alongside the single standard action.
+    assert _staggered_filter((_foe("5foot_step"), _foe("attack"))) == (
+        _foe("5foot_step"),
+        _foe("attack"),
+    )
+
+
+def test_staggered_filter_keeps_only_one_move_or_standard() -> None:
+    # move then standard → the move wins (first move-or-standard).
+    assert _staggered_filter((_foe("move"), _foe("attack"))) == (_foe("move"),)
+    # standard then move → the standard wins.
+    assert _staggered_filter((_foe("attack"), _foe("move"))) == (_foe("attack"),)
+    # two standards → only the first survives.
+    assert _staggered_filter((_foe("attack"), _foe("attack"))) == (_foe("attack"),)
+
+
+def test_staggered_filter_drops_full_round_and_downgrades_full_attack() -> None:
+    # A leading full_attack collapses to a single standard attack (kept).
+    assert _staggered_filter((_foe("full_attack"),)) == (_foe("attack"),)
+    # A full-round charge is dropped; a following standard fills the slot.
+    assert _staggered_filter((_foe("charge"), _foe("attack"))) == (_foe("attack"),)
+    # full_attack after a spent slot is dropped (the slot is already used).
+    assert _staggered_filter((_foe("move"), _foe("full_attack"))) == (_foe("move"),)
+
+
 def test_nauseated_after_budget_keeps_single_move() -> None:
     # (move, attack, move): the budget drops the second move; the nauseated
     # filter then keeps only the first move and drops the standard attack.