Improve docs and testing.

Author: arik-so

ci/LDKSwift/Sources/LDKSwift/batteries/ChannelManagerConstructor.swift

@@ -103,7 +103,7 @@ public class ChannelManagerConstructor: NativeTypeWrapper {
     /**
      * A list of ChannelMonitors and the last block they each saw. You should sync the blockchain on each individually
      * starting with the block that builds on the hash given.
-     * After doing so (and syncing the blockchain on the channel manager as well), you should call chain_sync_completed()
+     * After doing so (and syncing the blockchain on the channel manager as well), you should call chainSyncCompleted()
      * and then continue to normal application operation.
      */
     public private(set) var channel_monitors: [(ChannelMonitor, [UInt8])]

ci/LDKSwift/Tests/LDKSwiftTests/LDKSwiftTests.swift

@@ -244,6 +244,7 @@ class LDKSwiftTests: XCTestCase {
         let channelOpenError = channelOpenResult.getError()!
         print("error type: \(channelOpenError.getValueType())")
 
+        // verify that error details can be accessed without memory access issues
         if let misuseError = channelOpenError.getValueAsApiMisuseError() {
             print("misuse error: \(misuseError.getErr())")
         } else if let unavailableError = channelOpenError.getValueAsChannelUnavailable() {