fix: /reasoning command — add gateway support, fix display, persist settings (#1031)

* fix: /reasoning command output ordering, display, and inline think extraction

Three issues with the /reasoning command:

1. Output interleaving: The command echo used print() while feedback
   used _cprint(), causing them to render out-of-order under
   prompt_toolkit's patch_stdout. Changed echo to use _cprint() so
   all output renders through the same path in correct order.

2. Reasoning display not working: /reasoning show toggled a flag
   but reasoning never appeared for models that embed thinking in
   inline <think> blocks rather than structured API fields. Added
   fallback extraction in _build_assistant_message to capture
   <think> block content as reasoning when no structured reasoning
   fields (reasoning, reasoning_content, reasoning_details) are
   present. This feeds into both the reasoning callback (during
   tool loops) and the post-response reasoning box display.

3. Feedback clarity: Added checkmarks to confirm actions, persisted
   show/hide to config (was session-only before), and aligned the
   status display for readability.

Tests: 7 new tests for inline think block extraction (41 total).

* feat: add /reasoning command to gateway (Telegram/Discord/etc)

The /reasoning command only existed in the CLI — messaging platforms
had no way to view or change reasoning settings. This adds:

1. /reasoning command handler in the gateway:
   - No args: shows current effort level and display state
   - /reasoning <level>: sets reasoning effort (none/low/medium/high/xhigh)
   - /reasoning show|hide: toggles reasoning display in responses
   - All changes saved to config.yaml immediately

2. Reasoning display in gateway responses:
   - When show_reasoning is enabled, prepends a 'Reasoning' block
     with the model's last_reasoning content before the response
   - Collapses long reasoning (>15 lines) to keep messages readable
   - Uses last_reasoning from run_conversation result dict

3. Plumbing:
   - Added _show_reasoning attribute loaded from config at startup
   - Propagated last_reasoning through _run_agent return dict
   - Added /reasoning to help text and known_commands set
   - Uses getattr for _show_reasoning to handle test stubs

run_agent.py

@@ -2442,6 +2442,16 @@ class AIAgent:
         """
         reasoning_text = self._extract_reasoning(assistant_message)
 
+        # Fallback: extract inline <think> blocks from content when no structured
+        # reasoning fields are present (some models/providers embed thinking
+        # directly in the content rather than returning separate API fields).
+        if not reasoning_text:
+            content = assistant_message.content or ""
+            think_blocks = re.findall(r'<think>(.*?)</think>', content, flags=re.DOTALL)
+            if think_blocks:
+                combined = "\n\n".join(b.strip() for b in think_blocks if b.strip())
+                reasoning_text = combined or None
+
         if reasoning_text and self.verbose_logging:
             preview = reasoning_text[:100] + "..." if len(reasoning_text) > 100 else reasoning_text
             logging.debug(f"Captured reasoning ({len(reasoning_text)} chars): {preview}")