validate mod structure when zip peeking

[Qubus0]

existence of mandatory files and also setting flags for optional ones (overrides)

todo from #416

[KANAjetzt]

We can rewrite load_manifest() to access the zip data.

godot-mod-loader/addons/mod_loader/resources/mod_data.gd

Lines 92 to 105 in 3a88966

	# Load meta data from a mod's manifest.json file
	func load_manifest() -> void:
	if not _has_required_files():
	return
	ModLoaderLog.info("Loading mod_manifest (manifest.json) for -> %s" % dir_name, LOG_NAME)
	# Load meta data file
	var manifest_path := get_required_mod_file_path(required_mod_files.MANIFEST)
	var manifest_dict := _ModLoaderFile.get_json_as_dict(manifest_path)
	var mod_manifest := ModManifest.new(manifest_dict)
	manifest = mod_manifest
	validate_manifest_loadability()

[KANAjetzt]

closed by #485