thalamus: interactive sampling parameter controls

F5 screen now shows temperature, top_p, top_k with interactive
adjustment:
- Up/down: select parameter
- Left/right: adjust value (0.05 steps for temp/top_p, 5 for top_k)
- Updates Agent and display immediately via HotkeyAction

Co-Authored-By: Proof of Concept <poc@bcachefs.org>

src/mind/mod.rs

@@ -928,6 +928,16 @@ pub async fn run(cli: crate::user::CliArgs) -> Result<()> {
                 HotkeyAction::KillProcess => session.kill_processes().await,
                 HotkeyAction::Interrupt => session.interrupt().await,
                 HotkeyAction::CycleAutonomy => session.cycle_autonomy(),
+                HotkeyAction::AdjustSampling(param, delta) => {
+                    if let Ok(mut agent) = session.agent.try_lock() {
+                        match param {
+                            0 => { agent.temperature = (agent.temperature + delta).clamp(0.0, 2.0); app.temperature = agent.temperature; }
+                            1 => { agent.top_p = (agent.top_p + delta).clamp(0.0, 1.0); app.top_p = agent.top_p; }
+                            2 => { agent.top_k = (agent.top_k as f32 + delta).max(0.0) as u32; app.top_k = agent.top_k; }
+                            _ => {}
+                        }
+                    }
+                }
             }
         }