FF Expert settings management for single Node-RED instance

**Parent Deliverable:** FlowFuse/product#47 — Expert as Agentic Co-pilot

### Description

Enable FF Expert to view, audit, and adjust Node-RED settings and FlowFuse-related Node-RED settings for a single instance when working in the immersive editor.

### User Story

As a FlowFuse user working in the immersive editor, I want FF Expert to help me understand and configure my Node-RED instance settings so that I can optimize my setup without manually navigating settings panels.

### Capabilities

**Audit:**
- Review current Node-RED settings and highlight potential issues
- Check FlowFuse-specific Node-RED configuration (launcher settings, etc.)
- Identify security or performance concerns in settings

**Adjust:**
- Modify Node-RED editor settings
- Update FlowFuse-related Node-RED configuration
- Apply recommended settings based on use case

### Scope

This issue is scoped to a **single Node-RED instance** accessed via the immersive editor. The Expert communicates with the NR Assistant to read and modify settings for that specific instance only.

### Prerequisites

- FlowFuse/flowfuse#6497 (communication between FF Expert and NR Assistant)

### Epic/Story

_No response_

### Have you provided an initial effort estimate for this issue?

I have provided an initial effort estimate