feat: fleet secrets manager

[jajeffries]

This pull request introduces support for integrating the Fleet-based secrets manager with the Fleet configuration manager, enabling secure secrets distribution over MQTT. It adds new types and message schemas for secrets management, updates the Fleet configuration manager to bind and handle secrets, and refactors several types and methods for consistency and extensibility. The changes also include improvements to topic handling in the MQTT connection and add necessary configuration fields for secrets management.

Fleet secrets manager integration

• Added logic in agent/agent.go to bind the Fleet secrets manager to the Fleet configuration manager when both are active, ensuring secrets can be resolved during configuration.
• Implemented BindSecretsManager in FleetConfigManager to register MQTT topic handlers and bind the secrets manager for secure communication.

Secrets message schema and configuration

• Introduced new message types and error codes for secrets operations in agent/configmgr/fleet/messages/secrets_messages.go, defining request, response, and update notification structures.
• Added FleetSecretsManager type and related configuration fields to support Fleet secrets manager options in agent/config/types.go.

MQTT connection enhancements

• Added topic handler registration and dispatching to MQTTConnection, allowing dynamic handling of secrets-related MQTT topics. [1] [2] [3] [4] [5]
• Updated topic templates and TokenResponseTopics to include secrets request, response, and update topics for proper routing. [1] [2] [3]

Refactoring and consistency

• Renamed fleetConfigManager to FleetConfigManager and updated related constructors and methods for clarity and adherence to Go naming conventions. [1] [2] [3] [4] [5] [6] [7]
• Updated test utilities to dynamically find available ports for more robust testing in agent/configmgr/fleet_test.go. [1] [2]

[github-actions]

Go test coverage

STATUS	ELAPSED	PACKAGE	COVER	PASS	FAIL	SKIP
🟢 PASS	1.05s	github.com/netboxlabs/orb-agent/agent	43.8%	6	0	0
🟢 PASS	31.89s	github.com/netboxlabs/orb-agent/agent/backend	75.2%	40	0	0
🟢 PASS	6.03s	github.com/netboxlabs/orb-agent/agent/backend/devicediscovery	67.3%	4	0	0
🟢 PASS	0.96s	github.com/netboxlabs/orb-agent/agent/backend/mocks	0.0%	0	0	0
🟢 PASS	6.03s	github.com/netboxlabs/orb-agent/agent/backend/networkdiscovery	59.0%	4	0	0
🟢 PASS	4.02s	github.com/netboxlabs/orb-agent/agent/backend/opentelemetryinfinity	45.2%	2	0	0
🟢 PASS	4.03s	github.com/netboxlabs/orb-agent/agent/backend/pktvisor	67.0%	2	0	0
🟢 PASS	6.04s	github.com/netboxlabs/orb-agent/agent/backend/snmpdiscovery	59.0%	4	0	0
🟢 PASS	7.04s	github.com/netboxlabs/orb-agent/agent/backend/worker	68.2%	5	0	0
🟢 PASS	1.01s	github.com/netboxlabs/orb-agent/agent/config	100.0%	6	0	0
🟢 PASS	1.37s	github.com/netboxlabs/orb-agent/agent/configmgr	48.2%	32	0	0
🟢 PASS	2.71s	github.com/netboxlabs/orb-agent/agent/configmgr/fleet	64.1%	141	0	0
🟢 PASS	1.02s	github.com/netboxlabs/orb-agent/agent/otlpbridge	42.2%	8	0	0
🟢 PASS	1.01s	github.com/netboxlabs/orb-agent/agent/policies	98.9%	18	0	0
🟢 PASS	1.03s	github.com/netboxlabs/orb-agent/agent/policymgr	71.6%	11	0	0
🟢 PASS	18.68s	github.com/netboxlabs/orb-agent/agent/secretsmgr	47.5%	65	0	0
🟢 PASS	1.02s	github.com/netboxlabs/orb-agent/agent/telemetry	81.7%	19	0	0
🟢 PASS	1.01s	github.com/netboxlabs/orb-agent/agent/version	100.0%	1	0	0

Total coverage: 58.5%

[leoparente]

maybe we need to discuss the agent design and the order that process happens. We bind and execute ConfigManager logic event before it was started.