Extensions: split add-ons & extensions into separate preferences

Add back the "Add-ons" preferences, removing add-on logic from
extensions.

- Add support for filtering add-ons by tags
  (separate from extension tags).
- Tags now respect the "Only Enabled" option.
- Remove the ability to enable/disable add-ons from extensions.
- Remove add-on preferences from extensions.
- Remove "Legacy" & "Core" prefix from add-on names.
- Remove "Show Legacy Add-ons" filtering option.

Implements design task #122735.

Details:

- Add-on names and descriptions are no longer translated,
  since it's impractical to translate text which is mostly
  maintained outside of Blender.
- Extensions names have a `[disabled]` suffix when disabled so it's
  possible to identify installed but disabled extensions.
- The add-on "type" is shown in the details,
  so it's possible to tell the difference between an extension,
  a core add-on & a legacy user add-on.
- Icons are also used to differentiate the add-on type.
- User add-on's must be uninstalled from the add-ons section
  (matching 4.1 behavior).
- Simplify logic for filtering tags, move into a function.

scripts/addons_core/bl_pkg/__init__.py

@@ -552,6 +552,10 @@ def register():
     bl_extension_ops.register()
     bl_extension_ui.register()
 
+    WindowManager.addon_tags = PointerProperty(
+        name="Addon Tags",
+        type=BlExtDummyGroup,
+    )
     WindowManager.extension_tags = PointerProperty(
         name="Extension Tags",
         type=BlExtDummyGroup,
@@ -583,11 +587,6 @@ def register():
         name="Show Installed Extensions",
         description="Only show installed extensions",
     )
-    WindowManager.extension_show_legacy_addons = BoolProperty(
-        name="Show Legacy Add-ons",
-        description="Show add-ons which are not packaged as extensions",
-        default=True,
-    )
 
     from bl_ui.space_userpref import USERPREF_MT_interface_theme_presets
     USERPREF_MT_interface_theme_presets.append(theme_preset_draw)
@@ -623,7 +622,6 @@ def unregister():
     del WindowManager.extension_type
     del WindowManager.extension_enabled_only
     del WindowManager.extension_installed_only
-    del WindowManager.extension_show_legacy_addons
 
     for cls in classes:
         bpy.utils.unregister_class(cls)

scripts/startup/bl_operators/userpref.py

@@ -888,7 +888,7 @@ class PREFERENCES_OT_addon_show(Operator):
             bl_info = addon_utils.module_bl_info(mod)
             bl_info["show_expanded"] = True
 
-            context.preferences.active_section = 'EXTENSIONS'
+            context.preferences.active_section = 'ADDONS'
             context.preferences.view.show_addons_enabled_only = False
             context.window_manager.addon_filter = 'All'
             context.window_manager.addon_search = bl_info["name"]

scripts/startup/bl_ui/space_userpref.py

@@ -2261,6 +2261,23 @@ class USERPREF_PT_extensions_repos(Panel):
             layout_panel.prop(active_repo, "module")
 
 
+# -----------------------------------------------------------------------------
+# Extensions Panels
+
+class ExtensionsPanel:
+    bl_space_type = 'PREFERENCES'
+    bl_region_type = 'WINDOW'
+    bl_context = "extensions"
+
+
+class USERPREF_PT_extensions(ExtensionsPanel, Panel):
+    bl_label = "Extensions"
+    bl_options = {'HIDE_HEADER'}
+
+    def draw(self, context):
+        pass
+
+
 # -----------------------------------------------------------------------------
 # Add-on Panels
 
@@ -2279,7 +2296,7 @@ class USERPREF_PT_addons_filter(Panel):
 class AddOnPanel:
     bl_space_type = 'PREFERENCES'
     bl_region_type = 'WINDOW'
-    bl_context = "extensions"
+    bl_context = "addons"
 
 
 class USERPREF_PT_addons(AddOnPanel, Panel):
@@ -2950,6 +2967,7 @@ classes = (
 
     USERPREF_PT_keymap,
 
+    USERPREF_PT_extensions,
     USERPREF_PT_addons,
 
     USERPREF_MT_extensions_active_repo,

source/blender/makesdna/DNA_userdef_types.h

@@ -1142,7 +1142,7 @@ typedef enum eUserPref_Section {
   USER_SECTION_SYSTEM = 3,
   USER_SECTION_THEME = 4,
   USER_SECTION_INPUT = 5,
-  USER_SECTION_EXTENSIONS = 6,
+  USER_SECTION_ADDONS = 6,
   USER_SECTION_LIGHT = 7,
   USER_SECTION_KEYMAP = 8,
 #ifdef WITH_USERDEF_WORKSPACES
@@ -1155,6 +1155,7 @@ typedef enum eUserPref_Section {
   USER_SECTION_NAVIGATION = 14,
   USER_SECTION_FILE_PATHS = 15,
   USER_SECTION_EXPERIMENTAL = 16,
+  USER_SECTION_EXTENSIONS = 17,
 } eUserPref_Section;
 
 /** #UserDef_SpaceData.flag (State of the user preferences UI). */

source/blender/makesrna/intern/rna_userdef.cc

@@ -60,6 +60,7 @@ const EnumPropertyItem rna_enum_preference_section_items[] = {
     {USER_SECTION_ANIMATION, "ANIMATION", 0, "Animation", ""},
     RNA_ENUM_ITEM_SEPR,
     {USER_SECTION_EXTENSIONS, "EXTENSIONS", 0, "Extensions", ""},
+    {USER_SECTION_ADDONS, "ADDONS", 0, "Add-ons", ""},
     {USER_SECTION_THEME, "THEMES", 0, "Themes", ""},
 #if 0 /* def WITH_USERDEF_WORKSPACES */
     RNA_ENUM_ITEM_SEPR,