docs: finalize channel mode and shuffle docs

README.md

@@ -101,6 +101,9 @@ Discord extension capabilities: `docs/DISCORD_CONTROL.md`.
 /dirigent turn-status
 /dirigent turn-advance
 /dirigent turn-reset
+/dirigent turn-shuffling
+/dirigent turn-shuffling on
+/dirigent turn-shuffling off
 ```
 
 ---
@@ -116,8 +119,13 @@ Common options (see `docs/INTEGRATION.md`):
 - `waitIdentifier` (default `👤`) — agent ends with this to pause all agents until human replies
 - `channelPoliciesFile` (per-channel overrides)
 - `moderatorBotToken` (handoff messages)
+- `multiMessageStartMarker` (default `↗️`)
+- `multiMessageEndMarker` (default `↙️`)
+- `multiMessagePromptMarker` (default `⤵️`)
 - `enableDebugLogs`, `debugLogChannelIds`
 
+Shuffle mode does not currently have a global config key. It is a per-channel runtime toggle, defaults to off, and is controlled with `/dirigent turn-shuffling ...`.
+
 ---
 
 ## Development plan (incremental commits)