Synced from monorepo

Changes:
- Detect the herdr multiplexer
- Mark /gboom as non-production code
- Bound peak memory when loading a large session
- Add a subagent lifecycle soak bounding threads, fds, and heap
- Stream inherited replay to bound fork memory
- Copy full plan from plan approval with y
- Stop armed signature verification from deleting the managed-deny smoke policy
- Add source-tagged terminal version telemetry
- Show the UI instantly and fetch models and settings in the background
- Session test helpers
- computer_reason on the ConversationHistoryDone trailer

crates/codegen/xai-grok-pager/src/doctor_cmd/json.rs

@@ -379,6 +379,7 @@ pub(super) fn multiplexer(kind: MultiplexerKind) -> &'static str {
         MultiplexerKind::Screen => "screen",
         MultiplexerKind::Zellij => "zellij",
         MultiplexerKind::Cmux => "cmux",
+        MultiplexerKind::Herdr => "herdr",
         MultiplexerKind::Undetected => "undetected",
     }
 }

crates/codegen/xai-grok-pager/src/doctor_cmd/tests.rs

@@ -864,10 +864,11 @@ fn stable_mapping_tables_are_complete() {
             MultiplexerKind::Screen,
             MultiplexerKind::Zellij,
             MultiplexerKind::Cmux,
+            MultiplexerKind::Herdr,
             MultiplexerKind::Undetected,
         ]
         .map(multiplexer),
-        ["tmux", "screen", "zellij", "cmux", "undetected"]
+        ["tmux", "screen", "zellij", "cmux", "herdr", "undetected"]
     );
     assert_eq!(
         [