Say why a working method has nobody calling it

Setting a Kick channel's chat mode is a broadcaster's own setting and belongs
on Kick's site, beside the rest of the settings it sits with. So
`setKickChatMode` will not grow a caller - which is a decision about scope
rather than about the code, and the code works, so it stays.

Written at the method because that is where the next person looks. A coverage
review found this as an unreachable capability and filed it; without the
reason recorded here, the next sweep finds exactly the same thing and files it
again. That churn is what the last round of comment fixes existed to stop.

The distinction worth keeping straight is that *reading* the mode is a
different question and is answered: `ChatroomUpdatedEvent` keeps
followers-only, subscribers-only and slow mode current, which is how this
client can say why a message will not send.

Closes #167.

Co-Authored-By: Claude Opus 5 <[email protected]>

src/rpc/methods.rs

@@ -3115,6 +3115,17 @@ pub async fn dispatch(
         // not being changed are read back from what the channel already is
         // rather than guessed - a caller turning on slow mode must not
         // silently turn off followers-only on the way.
+        //
+        // **Deliberately has no caller, and should not grow one.** Setting a
+        // channel's chat mode is a broadcaster's own setting and belongs in
+        // Kick's dashboard, which is where it is done and where the rest of
+        // the settings beside it live (#167). Reading it is a different
+        // question and is done: `ChatroomUpdatedEvent` keeps the mode current
+        // (backend/kick/chat.rs) so this client can say why a message will
+        // not send. Kept rather than deleted because it works and the
+        // decision is about scope rather than about the code - and named here
+        // so a later sweep for unreachable methods finds the reason instead
+        // of re-filing the finding.
         "setKickChatMode" => {
             let (account_id, buffer_id) = match (p_str_opt(params, "accountId"), p_str_opt(params, "bufferId")) {
                 (Some(a), Some(b)) => (a, b),