chore: release version 2.3.5 and refactor lobby

Bump export_presets.cfg version to 2.3.5. Update CHANGELOG_DRAFT.md.
Refactor lobby.gd into LobbyChat, LobbyMainMenu, LobbyRoomList, LobbyRoom.
Move Nakama config to environment variables in nakama_manager.gd.
Derive auth_manager.gd encryption key from OS.get_unique_id().sha256_text().
Remove Steam email auth fallback. Require auth ticket.
Make GachaManager.pull() async in gacha_panel.gd.
Remove dummy wallet seeding. Add store_type to IAP payload.
Validate IAP receipts server-side in economy.lua.
Register gacha module in main.lua.
Clean backend_service.gd stubs.
Fix featured_banners type safety in gacha_manager.gd. Guards non-array responses.
Move tiles_armagedon_a1.res to assets/models/meshes/. Fix import fallback_path.

addons/gut/autofree.gd

@@ -0,0 +1,86 @@
+# ##############################################################################
+#(G)odot (U)nit (T)est class
+#
+# ##############################################################################
+# The MIT License (MIT)
+# =====================
+#
+# Copyright (c) 2025 Tom "Butch" Wesley
+#
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+#
+# The above copyright notice and this permission notice shall be included in
+# all copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+# THE SOFTWARE.
+#
+# ##############################################################################
+# Class used to keep track of objects to be freed and utilities to free them.
+# ##############################################################################
+var _to_free = []
+var _to_queue_free = []
+var _ref_counted_doubles = []
+var _all_instance_ids = []
+
+
+func _add_instance_id(thing):
+	if(thing.has_method("get_instance_id")):
+		_all_instance_ids.append(thing.get_instance_id())
+
+
+func add_free(thing):
+	if(typeof(thing) == TYPE_OBJECT):
+		_add_instance_id(thing)
+		if(!thing is RefCounted):
+			_to_free.append(thing)
+		elif(GutUtils.is_double(thing)):
+			_ref_counted_doubles.append(thing)
+
+
+func add_queue_free(thing):
+	if(typeof(thing) == TYPE_OBJECT):
+		_add_instance_id(thing)
+		_to_queue_free.append(thing)
+
+
+func get_queue_free_count():
+	return _to_queue_free.size()
+
+
+func get_free_count():
+	return _to_free.size()
+
+
+func free_all():
+	for node in _to_free:
+		if(is_instance_valid(node)):
+			if(GutUtils.is_double(node)):
+				node.__gutdbl_done()
+			node.free()
+	_to_free.clear()
+
+	for i in range(_to_queue_free.size()):
+		if(is_instance_valid(_to_queue_free[i])):
+			_to_queue_free[i].queue_free()
+	_to_queue_free.clear()
+
+	for ref_dbl in _ref_counted_doubles:
+		ref_dbl.__gutdbl_done()
+	_ref_counted_doubles.clear()
+
+	_all_instance_ids.clear()
+
+
+func has_instance_id(id):
+	return _all_instance_ids.has(id)