feat: context pressure warnings for CLI and gateway (#2159)

* feat: context pressure warnings for CLI and gateway

User-facing notifications as context approaches the compaction threshold.
Warnings fire at 60% and 85% of the way to compaction — relative to
the configured compression threshold, not the raw context window.

CLI: Formatted line with a progress bar showing distance to compaction.
Cyan at 60% (approaching), bold yellow at 85% (imminent).

  ◐ context ▰▰▰▰▰▰▰▰▰▰▰▰▱▱▱▱▱▱▱▱ 60% to compaction  100k threshold (50%) · approaching compaction
  ⚠ context ▰▰▰▰▰▰▰▰▰▰▰▰▰▰▰▰▰▱▱▱ 85% to compaction  100k threshold (50%) · compaction imminent

Gateway: Plain-text notification sent to the user's chat via the new
status_callback mechanism (asyncio.run_coroutine_threadsafe bridge,
same pattern as step_callback).

Does NOT inject into the message stream. The LLM never sees these
warnings. Flags reset after each compaction cycle.

Files changed:
- agent/display.py — format_context_pressure(), format_context_pressure_gateway()
- run_agent.py — status_callback param, _context_50/70_warned flags,
  _emit_context_pressure(), flag reset in _compress_context()
- gateway/run.py — _status_callback_sync bridge, wired to AIAgent
- tests/test_context_pressure.py — 23 tests

* Merge remote-tracking branch 'origin/main' into hermes/hermes-7ea545bf

---------

Co-authored-by: Test <test@test.com>

gateway/run.py

@@ -4539,6 +4539,26 @@ class GatewayRunner:
             except Exception as _e:
                 logger.debug("agent:step hook error: %s", _e)
 
+        # Bridge sync status_callback → async adapter.send for context pressure
+        _status_adapter = self.adapters.get(source.platform)
+        _status_chat_id = source.chat_id
+        _status_thread_metadata = {"thread_id": source.thread_id} if source.thread_id else None
+
+        def _status_callback_sync(event_type: str, message: str) -> None:
+            if not _status_adapter:
+                return
+            try:
+                asyncio.run_coroutine_threadsafe(
+                    _status_adapter.send(
+                        _status_chat_id,
+                        message,
+                        metadata=_status_thread_metadata,
+                    ),
+                    _loop_for_step,
+                )
+            except Exception as _e:
+                logger.debug("status_callback error (%s): %s", event_type, _e)
+
         def run_sync():
             # Pass session_key to process registry via env var so background
             # processes can be mapped back to this gateway session
@@ -4631,6 +4651,7 @@ class GatewayRunner:
                 tool_progress_callback=progress_callback if tool_progress_enabled else None,
                 step_callback=_step_callback_sync if _hooks_ref.loaded_hooks else None,
                 stream_delta_callback=_stream_delta_cb,
+                status_callback=_status_callback_sync,
                 platform=platform_key,
                 honcho_session_key=session_key,
                 honcho_manager=honcho_manager,