chore(tooling): install GUT v9.6.0 test framework

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

addons/gut/gut_loader.gd

@@ -0,0 +1,75 @@
+# ------------------------------------------------------------------------------
+# This script has been greatly simplified by Godot 4.6's ability to include or
+# exclude individual directories.  This now just excludes the gut directory
+# right off the bat and that's about it.
+#
+# This script should be loaded as soon as possible when running tests.  This
+# will disable warnings and then load all scripts that are registered with the
+# LazyLoader.  This also adds res://addons/gut to directory_rules for exclusion.
+##
+# This was created after a first attempt to suppress all GUT warnings did not
+# work for the strictest warning settings.  This has turned the LazyLoader into
+# just a Loader...so maybe all that should be reworked or renamed.  A problem
+# for a time when we are absolutely sure that all warnings are being correctly
+# suppressed I suppose.
+#
+# You can use the cli script addons/gut/cli/change_project_warnings.gd to
+# quickly alter project warning levels for testing purposes.
+# 	gdscript addons/gut/cli/change_project_warnings.gd --headless ++ -h
+#
+# You can set project warning settings from the command line with:
+#	godot -s addons/gut/cli/change_project_warnings.gd ++ -h
+#
+# This script should conform to, or ignore, the strictest warning settings.
+# ------------------------------------------------------------------------------
+const WARNING_PATH : String = 'debug/gdscript/warnings/'
+
+
+@warning_ignore("unsafe_method_access")
+@warning_ignore("unsafe_property_access")
+@warning_ignore("untyped_declaration")
+static func _static_init() -> void:
+	var WarningsManager = load('res://addons/gut/warnings_manager.gd')
+	if(!WarningsManager.disabled):
+		WarningsManager.exclude_gut()
+		WarningsManager.exclude_dynamic_files()
+
+	# Force a reference to utils.gd by path.  Using the class_name would cause
+	# utils.gd to load when this script loads, before we could turn off the
+	# warnings.
+	var _utils : Object = load('res://addons/gut/utils.gd')
+
+	# Since load_all exists on the LazyLoader, it should be done now so nothing
+	# sneaks in later...This essentially defeats the "lazy" part of the
+	# LazyLoader, but not the "loader" part of LazyLoader.
+	_utils.LazyLoader.load_all()
+
+
+# ##############################################################################
+# (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.
+#
+# ##############################################################################