Followed hashtags, and a tag's week of use

tags/:name shows the tag's last seven days in public posts PrivaPub holds
(uses and authors, as Mastodon gives them) and whether the persona follows
it; follow, unfollow and followed_tags replace the stubs. A public post that
is neither a boost nor a reply comes, as it arrives, to the homes of those
following one of its tags. Nothing is fetched for a followed tag and no
other server hears of it. Posts are indexed by tag.

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

PrivaPub/Models/Social/FollowedTag.cs

@@ -0,0 +1,13 @@
+using MongoDB.Entities;
+
+namespace PrivaPub.Models.Social
+{
+	//a hashtag a persona follows (Mastodon's followed tags, owner decision 2026-10-04): public posts PrivaPub holds with it
+	//come to the persona's home as they arrive. Following one fetches nothing and tells no other server.
+	public class FollowedTag : Entity
+	{
+		public string AvatarId { get; set; }
+		public string Name { get; set; }//normalised: no #, NFKC, lower case
+		public DateTime CreatedAt { get; set; } = DateTime.UtcNow;
+	}
+}