Fix: "Retrieving nodes" significantly slower after reconnect extracted from #1424 (#1477)

* Fix: "Retrieving nodes" significantly slower after reconnect (#1424)

The node database retrieval was calling context.save() for every single
NodeInfo packet received (250 saves for 250 nodes). This caused severe
performance degradation on reconnect when CoreData had accumulated state.

Root Cause:
- nodeInfoPacket() called context.save() immediately for each node
- With 250 nodes, this meant 250 individual CoreData save operations
- On first connection, CoreData is fresh and fast
- On reconnect, CoreData has accumulated change tracking, undo management,
  and memory pressure, making each save progressively slower
- This resulted in 10+ second retrieval times vs 1-2 seconds initially

Solution:
- Added deferSave parameter to nodeInfoPacket() function
- During database retrieval (.retrievingDatabase state), defer all saves
- Perform a single batch save when database retrieval completes
  (when NONCE_ONLY_DB configCompleteID is received)
- This reduces 250 saves to 1 save

Performance Impact:
- Eliminates N individual saves during node database sync
- Reduces database retrieval time back to 1-2 seconds on reconnect
- Matches first-connection performance consistently

Fixes #1424

* Revert *MessageListUnified files

---------

Co-authored-by: Martin Bogomolni <martinbogo@gmail.com>
Co-authored-by: Jake-B <jake-b@users.noreply.github.com>

Meshtastic/Accessory/Accessory Manager/AccessoryManager+FromRadio.swift

@@ -106,8 +106,11 @@ extension AccessoryManager {
 			return
 		}
 
+		// Check if we're in database retrieval mode to defer saves for performance
+		let isRetrievingDatabase = if case .retrievingDatabase = self.state { true } else { false }
+		
 		// TODO: nodeInfoPacket's channel: parameter is not used
-		if let nodeInfo = nodeInfoPacket(nodeInfo: nodeInfo, channel: 0, context: context) {
+		if let nodeInfo = nodeInfoPacket(nodeInfo: nodeInfo, channel: 0, context: context, deferSave: isRetrievingDatabase) {
 			if let activeDevice = activeConnection?.device, activeDevice.num == nodeInfo.num {
 				if let user = nodeInfo.user {
 					updateDevice(deviceId: activeDevice.id, key: \.shortName, value: user.shortName ?? "?")

Meshtastic/Accessory/Accessory Manager/AccessoryManager.swift

@@ -665,6 +665,17 @@ class AccessoryManager: ObservableObject, MqttClientProxyManagerDelegate {
 					self.firstDatabaseNodeInfoContinuation = nil
 				}
 				
+				// Perform a single batch save after database retrieval completes
+				// This significantly improves performance on reconnect
+				do {
+					try context.save()
+					Logger.data.info("💾 [Database] Batch saved all node info after database retrieval")
+				} catch {
+					context.rollback()
+					let nsError = error as NSError
+					Logger.data.error("💥 [Database] Error saving batch node info: \(nsError, privacy: .public)")
+				}
+				
 			default:
 				Logger.transport.error("[Accessory] Unknown nonce completed: \(configCompleteID)")
 			}

Meshtastic/Helpers/MeshPackets.swift

@@ -264,7 +264,7 @@ func deviceMetadataPacket (metadata: DeviceMetadata, fromNum: Int64, sessionPass
 	}
 }
 
-func nodeInfoPacket (nodeInfo: NodeInfo, channel: UInt32, context: NSManagedObjectContext) -> NodeInfoEntity? {
+func nodeInfoPacket (nodeInfo: NodeInfo, channel: UInt32, context: NSManagedObjectContext, deferSave: Bool = false) -> NodeInfoEntity? {
 
 	let logString = String.localizedStringWithFormat("[NodeInfo] received for: %@".localized, String(nodeInfo.num))
 	Logger.mesh.info("📟 \(logString, privacy: .public)")
@@ -375,8 +375,10 @@ func nodeInfoPacket (nodeInfo: NodeInfo, channel: UInt32, context: NSManagedObje
 					newNode.myInfo = fetchedMyInfo[0]
 				}
 				do {
-					try context.save()
-					Logger.data.info("💾 Saved a new Node Info For: \(String(nodeInfo.num), privacy: .public)")
+					if !deferSave {
+						try context.save()
+						Logger.data.info("💾 Saved a new Node Info For: \(String(nodeInfo.num), privacy: .public)")
+					}
 					return newNode
 				} catch {
 					context.rollback()
@@ -500,8 +502,10 @@ func nodeInfoPacket (nodeInfo: NodeInfo, channel: UInt32, context: NSManagedObje
 					fetchedNode[0].myInfo = fetchedMyInfo[0]
 				}
 				do {
-					try context.save()
-					Logger.data.info("💾 [NodeInfo] saved for \(nodeInfo.num.toHex(), privacy: .public)")
+					if !deferSave {
+						try context.save()
+						Logger.data.info("💾 [NodeInfo] saved for \(nodeInfo.num.toHex(), privacy: .public)")
+					}
 					return fetchedNode[0]
 				} catch {
 					context.rollback()