A handle finds its account, not posts and a made-up hashtag

Since status search by words, searching "@name@host" also answered posts
sharing the handle's words and a hashtag "#@name@host" made of the query,
so a client that opens the profile when the account is the only result
(decePub's search) stayed on the list. A handle now searches accounts only,
and a hashtag result is offered only when the query is one (letters, marks,
digits and underscores, with a letter).

Found by decePub's end-to-end tests: every profile follow test failed.

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

PrivaPub.Tests/Http/MastodonWordSearchTests.cs

@@ -46,5 +46,23 @@ namespace PrivaPub.Tests.Http
 			Assert.Equal(new[] { named },
 				(await reader.Client.Get($"/api/v2/search?q={word}&type=statuses&limit=1&offset=1")).Ok().Body["statuses"]!.AsArray().Select(s => s.Text("id")));
 		}
+
+		// a handle asks for its account: no posts sharing its words, and no hashtag made of it
+		[Fact]
+		public async Task A_handle_finds_its_account_and_neither_posts_nor_a_hashtag()
+		{
+			var reader = await _host.Mastodon("reader");
+			var named = await _host.Mastodon("named");
+			await reader.Status($"talking of {named.UserName} here");
+
+			foreach (var q in new[] { $"@{named.UserName}", $"@{named.UserName}@{PrivaPubHost.Host}", $"{named.UserName}@{PrivaPubHost.Host}" })
+			{
+				var body = (await reader.Client.Get($"/api/v2/search?q={Uri.EscapeDataString(q)}")).Ok().Body;
+				Assert.Contains(body["accounts"]!.AsArray(), a => a.Text("id") == named.Id);
+				Assert.Empty(body["statuses"]!.AsArray());
+				Assert.Empty(body["hashtags"]!.AsArray());
+			}
+			Assert.Equal("cats", Assert.Single((await reader.Client.Get("/api/v2/search?q=%23Cats")).Ok().Body["hashtags"]!.AsArray()).Text("name"));
+		}
 	}
 }