Accessorymanager background discovery

[garthvh]

Don't append new devices to the list of discovered devices if the app is in the background, seems to cause crashes

[Copilot]

Pull request overview

This PR addresses crashes caused by appending new devices to the discovery list when the app is in the background. The solution introduces a background state flag that prevents device list modifications during background/inactive states.

Key Changes

• Added isInBackground flag tracking in AccessoryManager based on scene phase
• Version bumped from 2.7.6 to 2.7.7 across all targets

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 2 comments.

File	Description
Meshtastic/MeshtasticApp.swift	Added logic to set accessoryManager.isInBackground flag when scene phase changes, preventing device discovery updates when app is not active
Meshtastic.xcodeproj/project.pbxproj	Updated marketing version from 2.7.6 to 2.7.7 across all build configurations and targets

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[compumike]

@garthvh FYI this change seems to break automatic reconnection when the app is in the background: shouldAutomaticallyConnectToPreferredPeripheral / connectToPreferredDevice relies on it being present in devices.

Test sequence:

• connect to a node (BLE)
• put app in background
• reboot the node
• watch the app logs

With this PR, it just stops at [Discovery] Found preferred peripheral and doesn't attempt to reconnect.