fix(chat): #363 — retail 0x1A typing for command refusals via the interface-text seam

ChatVM gains an OnInterfaceText hook + ShowInterfaceText(text), the
App-layer composition wires it to RuntimeCommunicationState.AddText,
and ChatCommandRouter routes every retail-0x1A command refusal through
it instead of the chat log's 0x00 sink. UI.Abstractions still never
references Runtime directly; unwired hosts (headless, tests) fall back
to the chat log tagged ClientLocal so no text is ever silently lost.

Reclassified per register row AP-183 (DoChannelList/On/Off, DoAllegiance,
DoHouseAvailableList — the last also corrected to retail's own bad-house-
type string instead of a synthesized "Usage:" line) and newly wired two
sites that previously showed nothing at all (DoStupidChannelHack's bare
legacy-channel-verb refusal, DoReply's message-but-no-last-teller
refusal). The generic bad-args fallback now resolves WeenieErrorMessages
0x026 ("That is not a valid command.", retail's HandleFailureEvent(0x26))
instead of synthesizing "Usage: {Usage}". DoSpeaker/DoEndurance/DoTitle
are untouched — already correct at 0x00.

Also closes #367 (DoHelp's "Unknown command" fallback and the degenerate-
prefix refusal now reach the SpewBox too) and retires register row
AP-186, whose own filing proposed exactly this seam shape.

Full Release suite: 12,542 passed / 4 skipped / 0 failed (baseline
12,466/4/0 at ff2784ea).

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

src/AcDream.UI.Abstractions/Panels/Chat/ChatInputParser.cs

@@ -124,6 +124,64 @@ public static class ChatInputParser
         ("/o",                ChatChannelKind.Olthoi),
     };
 
+    /// <summary>
+    /// The six retail channel groups whose registered-verb handler is
+    /// <c>ClientCommunicationSystem::DoStupidChannelHack @0x0057B144</c>
+    /// (command-registry doc §2.3) — the legacy 0x0147 channels. The
+    /// Turbine-only channels (General/Trade/Lfg/Roleplay/Society/Olthoi)
+    /// are never this handler's clients. <see cref="ChatChannelKind.Allegiance"/>
+    /// (retail's <c>@a</c>) still belongs here even though acdream always
+    /// sends it over Turbine once connected (<see cref="ChatChannelKind"/>'s
+    /// own doc comment) — DoStupidChannelHack dispatches on the REGISTERED
+    /// VERB, before Turbine send-time routing decides where the text goes;
+    /// retail's <c>"a"</c>/<c>"ab"</c> are one registered verb group.
+    /// </summary>
+    private static readonly HashSet<ChatChannelKind> LegacyChannelHackKinds =
+    [
+        ChatChannelKind.Fellowship,
+        ChatChannelKind.Allegiance,
+        ChatChannelKind.AllegianceBroadcast,
+        ChatChannelKind.Vassals,
+        ChatChannelKind.Patron,
+        ChatChannelKind.Monarch,
+        ChatChannelKind.CoVassals,
+    ];
+
+    /// <summary>
+    /// True when <paramref name="trimmed"/> is one of the
+    /// <see cref="LegacyChannelHackKinds"/> verbs with NO message — retail's
+    /// <c>DoStupidChannelHack</c> "You must specify the text you wish to
+    /// say!" refusal (<c>0x1A</c> ClientLocal,
+    /// acclient_2013_pseudo_c.txt:1030730, data_7da9b0). This parser stays
+    /// pure (no side effects — <see cref="Parse"/> just returns
+    /// <see langword="null"/> for this shape); <see cref="ChatCommandRouter"/>
+    /// owns the actual refusal text and routes it to the SpewBox.
+    /// </summary>
+    public static bool IsBareRegisteredChannelVerb(string trimmed)
+    {
+        foreach (var (verb, channel) in ChannelVerbs)
+        {
+            if (LegacyChannelHackKinds.Contains(channel) && IsBareVerb(trimmed, [verb]))
+                return true;
+        }
+
+        return false;
+    }
+
+    /// <summary>
+    /// True when <paramref name="trimmed"/> is <c>/reply</c>/<c>/r</c>/
+    /// <c>/rp</c> WITH a message but no prior incoming Tell — retail's
+    /// <c>ClientCommunicationSystem::DoReply @0x00577910</c> "Someone must
+    /// @tell you first!" refusal (<c>0x1A</c> ClientLocal,
+    /// acclient_2013_pseudo_c.txt:387538, data_7da974), the
+    /// <c>gmCCommunicationSystem::GetLastTeller() == 0</c> branch. Bare
+    /// <c>/r</c> with no message at all is a DIFFERENT retail branch (its
+    /// own copy of the "you must specify text" string) and is deliberately
+    /// out of scope here — not named by register row AP-183 / issue #363.
+    /// </summary>
+    public static bool IsReplyMissingLastTeller(string trimmed, string? lastTellSender) =>
+        string.IsNullOrEmpty(lastTellSender) && TryParseMessageOnly(trimmed, ReplyAliases, out _);
+
     /// <summary>
     /// Parse <paramref name="raw"/> into a <see cref="ParsedInput"/>
     /// triple, or <c>null</c> if the input is empty / whitespace /