Reverted to old "is action for armature" functionality

The current Blender 4.4 functionality is still very wishy washy (not able to inspect channel bags), and the solution that was created was broken.

In addition, newly created actions will be given an appropriately named slot instead of it being a "Legacy Slot".

io_scene_psk_psa/psa/export/operators.py

@@ -2,6 +2,7 @@ from collections import Counter
 from typing import List, Iterable, Dict, Tuple, cast as typing_cast
 
 import bpy
+import re
 from bpy.props import StringProperty
 from bpy.types import Context, Action, Object, AnimData, TimelineMarker, Operator, Armature
 from bpy_extras.io_utils import ExportHelper
@@ -16,7 +17,6 @@ from .ui import PSA_UL_export_sequences
 from ..builder import build_psa, PsaBuildSequence, PsaBuildOptions
 from ..writer import write_psa
 from ...shared.helpers import populate_bone_collection_list, get_nla_strips_in_frame_range, PsxBoneCollection
-from ...shared.semver import SemanticVersion
 from ...shared.ui import draw_bone_filter_mode
 
 
@@ -41,30 +41,18 @@ def is_action_for_object(obj: Object, action: Action):
     if obj is None or obj.animation_data is None or obj.type != 'ARMATURE':
         return False
 
-    version = SemanticVersion(bpy.app.version)
+    armature_data = typing_cast(Armature, obj.data)
+    bone_names = set([x.name for x in armature_data.bones])
     
-    def is_action_for_object_legacy(action: Action,  obj: Object):
-        """
-        This is the legacy behavior before slotted actions were introduced in Blender 4.4.
-        It would simply check if it had any f-curves that corresponded to any bones in the armature.
-        """
-        import re
-        armature_data = typing_cast(Armature, obj.data)
-        bone_names = set([x.name for x in armature_data.bones])
-        for fcurve in action.fcurves:
-            match = re.match(r'pose\.bones\[\"([^\"]+)\"](\[\"([^\"]+)\"])?', fcurve.data_path)
-            if not match:
-                continue
-            bone_name = match.group(1)
-            if bone_name in bone_names:
-                return True
-        return False
+    for fcurve in action.fcurves:
+        match = re.match(r'pose\.bones\[\"([^\"]+)\"](\[\"([^\"]+)\"])?', fcurve.data_path)
+        if not match:
+            continue
+        bone_name = match.group(1)
+        if bone_name in bone_names:
+            return True
     
-    if version < SemanticVersion((4, 4, 0)):
-        return is_action_for_object_legacy(action, obj)
-
-    # If the object is a part of the slot's user list, then it is a valid action for the object.
-    return any(obj in slot.users() for slot in action.slots)
+    return False
 
 
 def update_actions_and_timeline_markers(context: Context, armature_objects: Iterable[Object]):

io_scene_psk_psa/psa/importer.py

@@ -252,6 +252,7 @@ def import_psa(context: Context, psa_reader: PsaReader, armature_object: Object,
             action = bpy.data.actions[action_name]
         else:
             action = bpy.data.actions.new(name=action_name)
+            action.slots.new('OBJECT', armature_object.name)
 
         # Calculate the target FPS.
         match options.fps_source: