feat: send diode data over MQTT

[jajeffries]

This pull request introduces support for a new telemetry MQTT topic in the fleet configuration manager and related agent components. The main changes ensure that when running with the fleet config manager, the agent automatically configures the OTLP gRPC URL and handles the new telemetry topic throughout the configuration, bridge server, and tests. The update improves observability and integration with telemetry pipelines.

Fleet configuration and topic management:

• Added support for a new telemetry MQTT topic across configuration, topic templates, and token response structures, ensuring it is generated and available alongside existing topics. [1] [2] [3]
• Updated the fleet config manager to include and propagate the telemetry topic during initialization and bridge setup, and improved logging to show both ingest and telemetry topics. [1] [2]

Agent startup and OTLP configuration:

• Enhanced the agent startup logic to automatically override or create the OTLP gRPC URL as localhost:4317 when the fleet config manager is active, ensuring consistent backend configuration.

Bridge server enhancements:

• Extended the BridgeServer to store and manage the telemetry topic, with new setter and getter methods for thread-safe access. [1] [2]

Testing improvements:

• Added and updated tests to verify correct handling of the telemetry topic in topic generation, bridge initialization, and agent startup scenarios, including edge cases for missing configuration sections. [1] [2] [3] [4] [5] [6] [7] [8] [9] [10] [11] [12]

[github-actions]

Go test coverage

STATUS	ELAPSED	PACKAGE	COVER	PASS	FAIL	SKIP
🟢 PASS	1.06s	github.com/netboxlabs/orb-agent/agent	43.1%	5	0	0
🟢 PASS	1.11s	github.com/netboxlabs/orb-agent/agent/backend	33.3%	30	0	0
🟢 PASS	5.03s	github.com/netboxlabs/orb-agent/agent/backend/devicediscovery	68.7%	3	0	0
🟢 PASS	0.90s	github.com/netboxlabs/orb-agent/agent/backend/mocks	0.0%	0	0	0
🟢 PASS	5.04s	github.com/netboxlabs/orb-agent/agent/backend/networkdiscovery	59.9%	3	0	0
🟢 PASS	4.03s	github.com/netboxlabs/orb-agent/agent/backend/opentelemetryinfinity	46.3%	2	0	0
🟢 PASS	4.03s	github.com/netboxlabs/orb-agent/agent/backend/pktvisor	67.0%	2	0	0
🟢 PASS	5.03s	github.com/netboxlabs/orb-agent/agent/backend/snmpdiscovery	59.9%	3	0	0
🟢 PASS	6.04s	github.com/netboxlabs/orb-agent/agent/backend/worker	69.6%	4	0	0
🟢 PASS	1.02s	github.com/netboxlabs/orb-agent/agent/config	100.0%	6	0	0
🟢 PASS	31.46s	github.com/netboxlabs/orb-agent/agent/configmgr	47.5%	28	0	0
🟢 PASS	7.63s	github.com/netboxlabs/orb-agent/agent/configmgr/fleet	66.0%	137	0	0
🟢 PASS	1.02s	github.com/netboxlabs/orb-agent/agent/otlpbridge	29.5%	5	0	0
🟢 PASS	1.02s	github.com/netboxlabs/orb-agent/agent/policies	100.0%	15	0	0
🟢 PASS	1.03s	github.com/netboxlabs/orb-agent/agent/policymgr	71.6%	11	0	0
🟢 PASS	32.34s	github.com/netboxlabs/orb-agent/agent/secretsmgr	48.9%	54	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: 57.4%