Moves carry follows over; first DMs to Lemmy 0.19 and Mbin go as ChatMessage

Two owner decisions of 2026-10-05, both recorded in ROADMAP:
- After a verified Move the personas following the old account follow the new one, in the same lists, and a mute or
  block of the old account carries over, as Mastodon does it.
- A direct message to one account on a server whose NodeInfo names Lemmy before 1.0 or Mbin goes as a ChatMessage,
  the one place PrivaPub decides by a server's software (invariant 17). G-0008 is closed.

Mbin addresses its private messages to the recipient's profile page, so a Create addressed to a persona's /@name now
reaches the persona. Checked live: moves 8/8, Lemmy 0.19 30/30, Mbin 26/26 with messages both ways. The software
theory runs alone, since every test's peer shares 127.0.0.1.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01LsXgEaXee4GCU1hwYgPJXw

PrivaPub/Models/Jobs/RemoteInstance.cs

@@ -11,7 +11,8 @@ namespace PrivaPub.Models.Jobs
 		public DateTime? LastFailureAt { get; set; }
 		public string LastError { get; set; }
 
-		public string Software { get; set; }//NodeInfo software.name: for display, never for deciding behaviour
+		public string Software { get; set; }//NodeInfo software.name: for display, never for deciding behaviour, but for the one
+		//owner decision (2026-10-05) that a first private message to Lemmy before 1.0 or Mbin is a ChatMessage
 		public string SoftwareVersion { get; set; }
 		public string NodeName { get; set; }
 		public List<string> Protocols { get; set; } = new();