Cache `Module` to `Edge` relation in `ModuleManager`

[github-actions]

The Module to Edge relation is very unlikely to change, so keeping a lookup will save a lot of queries, especially with a high volume of executes.

To ensure correctness, updates to edge_id MUST be captured in a change listener.
A simple place to do so would be below...

core/src/placeos-core/mappings/module_names.cr

Lines 17 to 24 in b938d43

	def process_resource(action : RethinkORM::Changefeed::Event, resource mod : PlaceOS::Model::Module) : Resource::Result
	return Resource::Result::Skipped unless action.updated?
	ModuleNames.update_module_mapping(mod, module_manager)
	rescue exception
	Log.error(exception: exception) { {message: "while updating mapping for module", name: mod.name, custom_name: mod.custom_name} }
	raise Resource::ProcessingError.new(mod.name, exception.message, cause: exception)
	end

However, to ensure encapsulation and ease of testing, a separate listener on the modules table can be initiated.

An alternative to a listener would be ensuring that edge_id cannot be changed via mass assignment, and it can be assumed to be static, removing the need to consider cache stagnation.

Corresponding TODO

core/src/placeos-core/module_manager.cr

Lines 256 to 262 in b938d43

	edge_id = case mod
	in Model::Module
	mod.edge_id if mod.on_edge?
	in String
	# TODO: Cache `Module` to `Edge` relation in `ModuleManager`
	Model::Module.find!(mod).edge_id if Model::Module.has_edge_hint?(mod)
	end