Migrate TrueNAS apps to JSON-RPC 2.0 WebSocket API

[jaycollett]

Summary

TrueNAS is deprecating the REST API (api/v2.0/) in version 26.04, requiring migration to JSON-RPC 2.0 over WebSocket. This PR updates TrueNAS CORE and SCALE apps to support the new API.

Dependency

⚠️ This PR requires linuxserver/Heimdall#1538 to be merged first

That PR adds the WebSocket client infrastructure this PR depends on.

Changes

New Files

• TrueNASCORE/TrueNASApiTrait.php - Shared trait for WebSocket/REST API communication

Updated Files

• TrueNASCORE/TrueNASCORE.php - Updated to use the shared trait
• TrueNASCORE/config.blade.php - Added API mode selector
• TrueNASSCALE/TrueNASSCALE.php - Updated to use the shared trait
• TrueNASSCALE/config.blade.php - Added API mode selector

Features

API Mode Selection

Users can choose between three modes:

• Auto (default) - Tries WebSocket first, falls back to REST if unavailable
• WebSocket Only - For TrueNAS 25.04+ (fails if WebSocket unavailable)
• REST Only - For older TrueNAS versions or troubleshooting

API Mapping

REST Endpoint	JSON-RPC Method	Purpose
core/ping	core.ping	Connection test
system/info	system.info	Get uptime
alert/list	alert.list	Get alerts

Backward Compatibility

• Default mode is "Auto" which maintains compatibility with all TrueNAS versions
• Existing configurations continue to work without modification
• REST API support is preserved for users on older TrueNAS versions

TrueNAS Version	Recommended Mode
< 25.04	REST Only
25.04	Auto
26.04+	WebSocket Only (or Auto)

References

• Depends on: Add WebSocket support for TrueNAS JSON-RPC 2.0 API Heimdall#1538
• Related issue: truenas app still use the deprecated REST API Heimdall#1530
• TrueNAS JSON-RPC API Documentation

Test Plan

• Tested with TrueNAS SCALE 25.10.1 in WebSocket mode
• Verified API mode switching works correctly
• Confirmed livestats (uptime, alerts) work via WebSocket
• Tested with self-signed certificates
• Verified backward compatibility with REST mode

[mvdkleijn]

Sorry for the delay. I was busy working on https://opencommit.eu related stuff.

I have no control over linuxserver/Heimdall so I'll leave this open and unmerged.