R8 the Mastodon API made real in decePub: featured tags, notify, languages, recommendations, notes, suggestions, the direct stream

A profile shows the hashtags an account features as chips opening their feed; under another account's header is what the
persona keeps of it for itself alone: for one it follows, a bell (follow with notify), the languages of its posts that
reach the home feed (follow with languages[]) and Recommend (endorsements, private here), and for any account a private
note saved on blur or with Save. Settings edits the persona's featured hashtags (added by name or from those used lately,
10 at most) and its reading preferences (/clientapi/avatar/private/preferences), which CascadingState keeps per persona
and the card applies to sensitive media and content warnings. A hashtag's tab features it on the profile. Explore has Who
to follow (/api/v2/suggestions, dismissed for good after asking); Administration has Staff picks. The Direct tab follows
the direct stream's conversation events; status notifications show the post. The follows CSV carries notify and languages.

Verified: Release build, 0 errors (the 3 warnings were there before). Not run against PrivaPub or in the pasture.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01WpVCoDeM1qUTRp4fXQdfof

Models/Mastodon/InstanceV2.cs

@@ -37,6 +37,13 @@ public class InstanceRule
 public class InstanceConfiguration
 {
 	public MediaConfiguration MediaAttachments { get; set; } = new();
+	public AccountsConfiguration Accounts { get; set; } = new();
+}
+
+/// <summary>What an account may hold: how many hashtags it features on its profile (PrivaPub's 10).</summary>
+public class AccountsConfiguration
+{
+	public int MaxFeaturedTags { get; set; }
 }
 
 /// <summary>The types an upload may have and how big it may be, as the server enforces them.</summary>