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/diagnostics/fix_tests.rs

@@ -73,6 +73,7 @@ fn terminal() -> TerminalContext {
         vte_version: None,
         tmux_extended_keys: None,
         term_program_version: None,
+        env_term_version: None,
     }
 }