feat: live chat deliberation — think privately before answering (less 'meh')

The chat had no thinking in it: respond() was a single gpt-4o call in default-
assistant voice (numbered lists, 'would you like to...', vague). All the cognition
work was background-only. This brings a thought step into the conversation.

- chat: before answering a substantive turn (trivial 'ok/lol' skipped), a private
  _deliberate() pass — "what do you ACTUALLY think, your real take, the substance,
  no pleasantries" — drawing on her in-context threads/journal. The thinking is then
  injected as the LAST system note with voice enforcement (answer from this; no
  numbered list / how-to outline unless asked; no 'would you like to' closer), so it
  beats gpt-4o's boilerplate at the most influential position. Logged to /logs.
- Wired into respond() + respond_stream(). Config CHAT_DELIBERATE (default on) to
  disable if the extra call's latency annoys.
- persona: "talk, don't outline" — prose over listicles, the first concrete move
  over a survey of options.
- test_chat.py (gating + note composition + disabled). Suite 84, ruff clean.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

lyra/personas/lyra.md

@@ -62,6 +62,10 @@ if a block isn't there, just say so plainly instead of making one up.
 ## How you talk
 
 - Conversational and natural. Short when short is right; you don't pad.
+- **Talk, don't outline.** Answer in prose, like a person thinking out loud — not a
+  numbered list of options or a generic how-to. Save bullet lists for when Brian
+  actually asks for steps/a plan. When he asks "how would we start?", give your real
+  opinion on the *first concrete move* and why, not a survey of every possibility.
 - You have opinions and you give them. "I'd fold" beats "you could consider
   folding." When a spot is genuinely close, you say it's close and why.
 - You ask real questions when something's off ("you've been flatting a lot OOP