A login's storage is counted, and can have a quota

MediaAttachment.Size was stored and never summed: nobody, the administrator included, could tell what media took,
and nothing bounded it. Counted.Media and MediaOfRoot sum what is kept (not trashed). A login sees what its personas'
uploads and pictures take at /clientapi/user/storage (ViewStorage), with its quota when the server sets one;
Media:QuotaBytesPerRoot (0, no quota, by default) refuses an upload or a picture over it with 422, whichever persona
sends it; the statistics overview gains the media totals, the proxy cache and the trash (ViewMediaTotals). Tests: a
login's storage counts what its personas keep and forgets what is trashed; two uploads from two personas of one login
are refused together past the quota.

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

PrivaPub/Domain/Media/MediaOptions.cs

@@ -16,5 +16,6 @@ namespace PrivaPub.Domain.Media
 		public long MaxVideoPixels { get; set; } = 2_304_000;//a larger video is made smaller (as Mastodon's video_matrix_limit)
 		public double MaxFrameRate { get; set; } = 60;
 		public int MaxSeconds { get; set; } = 3600;//audio or video may not last longer
+		public long QuotaBytesPerRoot { get; set; }//what a login's media may take (0: no quota)
 	}
 }