Disable color theme reporting in tmux for now

Due to the way tmux implements it, color theme reporting
causes issues when typing commands really quickly (such as
when synthesizing keys).  We're working on fixing this, see
https://github.com/tmux/tmux/issues/4787#issuecomment-3707866550
Disable it for now. AFAIK other terminals are not affected.

Closes #12261

CHANGELOG.rst

@@ -5,6 +5,7 @@ This release fixes the following problems identified in fish 4.3.0:
 
 - Selecting a completion could insert only part of the token (:issue:`12249`).
 - Glitch with soft-wrapped autosuggestions and :doc:`cmds/fish_right_prompt` (:issue:`12255`).
+- Spurious echo in tmux when typing a command really fast (:issue:`12261`).
 - The sample prompts and themes are correctly installed (:issue:`12241`).
 - Last line of command output could be hidden when missing newline (:issue:`12246`).
 

src/tty_handoff.rs

@@ -184,8 +184,12 @@ fn get_protocols(self) -> TtyProtocolsSet {
             on_chain.push(DecsetFocusReporting);
             off_chain.push(DecrstFocusReporting);
         }
-        on_chain.extend_from_slice(&[DecsetBracketedPaste, DecsetColorThemeReporting]);
-        off_chain.extend_from_slice(&[DecrstBracketedPaste, DecrstColorThemeReporting]);
+        on_chain.push(DecsetBracketedPaste);
+        off_chain.push(DecrstBracketedPaste);
+        if self != TtyQuirks::Tmux {
+            on_chain.push(DecsetColorThemeReporting);
+            off_chain.push(DecrstColorThemeReporting);
+        }
 
         let on_chain = || on_chain.clone().into_iter();
         let off_chain = || off_chain.clone().into_iter();