Reorg of the cluster controller to new "Management framework" layout

- This gives the cluster controller and agent the common name "Management
framework" and changes the start directory of the sources from
"policy/frameworks/cluster" to "policy/frameworks/management". This avoids
ambiguity with the existing cluster framework.

- It renames the "ClusterController" and "ClusterAgent" script modules to
"Management::Controller" and "Management::Agent", respectively. This allows us
to anchor tooling common to both controller and agent at the "Management"
module.

- It moves common configuration settings, logging, requests, types, and
utilities to the common "Management" module.

- It removes the explicit "::Types" submodule (so a request/response result is
now a Management::Result, not a Management::Types::Result), which makes
typenames more readable.

- It updates tests that depend on module naming and full set of scripts.

scripts/policy/frameworks/management/controller/api.zeek

@@ -0,0 +1,119 @@
+##! The event API of cluster controllers. Most endpoints consist of event pairs,
+##! where the controller answers a zeek-client request event with a
+##! corresponding response event. Such event pairs share the same name prefix
+##! and end in "_request" and "_response", respectively.
+
+@load policy/frameworks/management/types
+
+module Management::Controller::API;
+
+export {
+	## A simple versioning scheme, used to track basic compatibility of
+	## controller, agents, and zeek-client.
+	const version = 1;
+
+
+	## zeek-client sends this event to request a list of the currently
+	## peered agents/instances.
+	##
+	## reqid: a request identifier string, echoed in the response event.
+	##
+	global get_instances_request: event(reqid: string);
+
+	## Response to a get_instances_request event. The controller sends
+	## this back to the client.
+	##
+	## reqid: the request identifier used in the request event.
+	##
+	## result: the result record. Its data member is a
+	##     :zeek:see:`Management::Instance` record.
+	##
+	global get_instances_response: event(reqid: string,
+	    result: Management::Result);
+
+
+	## zeek-client sends this event to establish a new cluster configuration,
+	## including the full cluster topology. The controller processes the update
+	## and relays it to the agents. Once each has responded (or a timeout occurs)
+	## the controller sends a corresponding response event back to the client.
+	##
+	## reqid: a request identifier string, echoed in the response event.
+	##
+	## config: a :zeek:see:`Management::Configuration` record
+	##     specifying the cluster configuration.
+	##
+	global set_configuration_request: event(reqid: string,
+	    config: Management::Configuration);
+
+	## Response to a set_configuration_request event. The controller sends
+	## this back to the client.
+	##
+	## reqid: the request identifier used in the request event.
+	##
+	## result: a vector of :zeek:see:`Management::Result` records.
+	##     Each member captures one agent's response.
+	##
+	global set_configuration_response: event(reqid: string,
+	    result: Management::ResultVec);
+
+
+	## zeek-client sends this event to request a list of
+	## :zeek:see:`Management::NodeStatus` records that capture
+	## the status of Supervisor-managed nodes running on the cluster's
+	## instances.
+	##
+	## reqid: a request identifier string, echoed in the response event.
+	##
+	global get_nodes_request: event(reqid: string);
+
+	## Response to a get_nodes_request event. The controller sends this
+	## back to the client.
+	##
+	## reqid: the request identifier used in the request event.
+	##
+	## result: a :zeek:type`vector` of :zeek:see:`Management::Result`
+	##     records. Each record covers one cluster instance. Each record's data
+	##     member is a vector of :zeek:see:`Management::NodeStatus`
+	##     records, covering the nodes at that instance. Results may also indicate
+	##     failure, with error messages indicating what went wrong.
+	global get_nodes_response: event(reqid: string,
+	    result: Management::ResultVec);
+
+
+	# Testing events. These don't provide operational value but expose
+	# internal functionality, triggered by test cases.
+
+	## This event causes no further action (other than getting logged) if
+	## with_state is F. When T, the controller establishes request state, and
+	## the controller only ever sends the response event when this state times
+	## out.
+	##
+	## reqid: a request identifier string, echoed in the response event when
+	##     with_state is T.
+	##
+	## with_state: flag indicating whether the controller should keep (and
+	##     time out) request state for this request.
+	##
+	global test_timeout_request: event(reqid: string, with_state: bool);
+
+	## Response to a test_timeout_request event. The controller sends this
+	## back to the client if the original request had the with_state flag.
+	##
+	## reqid: the request identifier used in the request event.
+	##
+	global test_timeout_response: event(reqid: string,
+	    result: Management::Result);
+
+
+	# Notification events, agent -> controller
+
+	## The controller triggers this event when the operational cluster
+	## instances align with the ones desired by the cluster
+	## configuration. It's essentially a cluster management readiness
+	## event. This event is currently only used by the controller and not
+	## published to other topics.
+	##
+	## instances: the set of instance names now ready.
+	##
+	global notify_agents_ready: event(instances: set[string]);
+	}