R4 the client catches up: follow requests, followers, downvotes, dismissing, filtering a post, quote policies, statistics in detail

Follow requests answered on the persona's own profile and from the Notifications tab; its followers and the accounts it
follows listed there, a follower removed (asked first). Downvotes on threadiverse posts, after the public-vote notice.
A notification dismissed from its line. "Filter this post" from a card's menu, and the Filters page showing the posts a
filter holds. Who may quote the persona's own posts, and revoking a quote of one. Statistics: a server in detail with
"describe again", the ledger's events, the server's own days. The composer deletes an upload taken out before posting.
MediaType.Documents goes.

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

Services/MediaService.cs

@@ -11,9 +11,10 @@ namespace decePubClient.Services
 {
 	/// <summary>
 	/// Uploads to PrivaPub (/api/v2/media, multipart), streamed from the browser's file; follows what it is still processing
-	/// (audio and video: 202, then 206 until ready); describes what isn't posted yet; and knows what PrivaPub takes.
+	/// (audio and video: 202, then 206 until ready); describes and deletes what isn't posted yet; and knows what PrivaPub
+	/// takes.
 	/// </summary>
-	public class MediaService(IHttpService httpService, CoalescingStringLocalizer localizer)
+	public class MediaService(IHttpService httpService, ILoggingService logger, CoalescingStringLocalizer localizer)
 	{
 		static readonly MediaConfiguration Fallback = new()
 		{
@@ -79,6 +80,20 @@ namespace decePubClient.Services
 			return new WebResult();
 		}
 
+		/// <summary>Deletes an upload of the persona's that no post holds (DELETE /api/v1/media/:id; PrivaPub refuses a posted
+		/// one with 422): the composer drops what was removed before posting. A failure is logged.</summary>
+		public async Task<WebResult> Discard(string mediaId, CancellationToken cancellationToken = default)
+		{
+			using var response = await httpService.Delete(APIs.Mastodon.DELETE_M_Media(mediaId), cancellationToken: cancellationToken);
+			if (response.IsSuccessStatusCode)
+				return new WebResult();
+
+			var result = await response.Content.ReadWebResult(response.StatusCode, localizer, cancellationToken);
+			if (result.StatusCode is not (int)HttpStatusCode.Gone)
+				await logger.ProcessWarning(result.ToString(localizer), $"{nameof(MediaService)}.{nameof(Discard)}", cancellationToken);
+			return result;
+		}
+
 		async Task<WebResult> Attachment(HttpResponseMessage response, CancellationToken cancellationToken)
 		{
 			var attachment = await response.MastodonReadFromJsonAsync<MediaAttachment>(cancellationToken);