feat: Add insights support

[Steve-Mcl]

Description

TLDR

Add support for MCP tasks (get features, call tool, read resource) command-able via the established command-response pattern (over MQTT) - thus permitting AI Insights Agent to request/execute MCP things via bridge.

Add support for requesting live-state from the device (via command-response pattern (over MQTT)) so that live state can be queried before attempting (and timing out) to get MCP features / execute MCP thing.

NOTE: To avoid adding the MCP SDK to the dependencies, they are loaded from the node_modules directory of the nr-mcp-server-nodes. The logic/reasoning is :-

1. the MCP SDK is a fast changing package
2. if mcp server nodes are not installed, there is no need for this lib to be installed or instantiated
3. version parity with MCP server nodes is maintained

Details

MCP SDK Integration and Lifecycle Management:

• The MQTT client (lib/mqtt.js) now instantiates an MCP helper, making MCP features available for MQTT command handling. [1] [2]
• The Launcher class (lib/launcher.js) now resets any cached MCP SDK reference both when starting and stopping, ensuring that the SDK is always up-to-date and not reused if the underlying files have changed. [1] [2]

New MQTT Command Support:

• The MQTT client now handles several new commands: get-liveState, mcp:get-features, mcp:call-tool, and mcp:read-resource, delegating these to the MCP helper and sending structured responses or errors as appropriate.

MQTT Command Response Improvements:

• The sendCommandResponse method now includes userProperties from the request in the response message, allowing for richer metadata propagation. [1] [2]

Dependency Management:

• The path module is now required in lib/mqtt.js to support MCP instantiation.

Related Issue(s)

Checklist

• I have read the contribution guidelines
• Suitable unit/system level tests have been added and they pass
• Documentation has been updated
  • Upgrade instructions
  • Configuration details
  • Concepts
• Changes flowforge.yml?
  • Issue/PR raised on FlowFuse/helm to update ConfigMap Template
  • Issue/PR raised on FlowFuse/CloudProject to update values for Staging/Production
• Link to Changelog Entry PR, or note why one is not needed.

Labels

• Includes a DB migration? -> add the area:migration label

[hardillb]

Confused with this name that it was msg.properties.userProperties (MQTTv5) not just a filed on the JSON in the msg.payload

[Steve-Mcl]

yes, you are correct. As device agent is currently (from inception) using the MQTT default protocol version v4 (3.1) v5 properties are not available. What we do to achieve req-resp pattern is to nest the payload in the MQTT payload (request object) and add the correlationData for tracking responses.
This addition here includes userProperties so that we have the ability to pass through (and pass back) any user properties that need to be carried through,

[hardillb]

Just a question about a command to clear up

And confirmation that this shouldn't need MQTTv5 for the userProperties stuff

[Steve-Mcl]

@hardillb hopefully answered yer questions (re-requested review)

[hardillb]

@Steve-Mcl approved, but @cstns should look at the mcp.js file

[Steve-Mcl]

@cstns check answers to comments & reply/resolve/suggest please - wanna get this moving.