fix: surface engine logs in dashboard TUI via console capture

The dashboard TUI Logs tab only showed the handful of lines emitted
through DashboardLogSink directly. Everything from @fusion/engine
(scheduler, executor, triage, merger, PR monitor, heartbeat, etc.)
logs via createLogger() which writes straight to console.error —
bypassing the sink. Under the TUI's alt screen those writes either
overdrew the frame or scrolled off, leaving the Logs tab near-empty.

DashboardLogSink now offers captureConsole() / releaseConsole():
while the TUI is running, console.log/warn/error are intercepted
and routed into the ring buffer. A leading `[prefix]` tag is
extracted so entries carry the subsystem name. Original console
functions are restored (by identity) on TUI shutdown.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

packages/cli/src/commands/dashboard.ts

@@ -388,6 +388,10 @@ export async function runDashboard(port: number, opts: { paused?: boolean; dev?:
 
     // Wire the TUI into the log sink so all console output routes through TUI
     logSink.setTUI(tui);
+    // Capture stdlib console.* so engine/scheduler/pi/etc. log lines (which
+    // go straight to console.error via createLogger in @fusion/engine) land
+    // in the TUI's ring buffer instead of being overwritten by the alt screen.
+    logSink.captureConsole();
   }
 
   store = new TaskStore(cwd);
@@ -794,6 +798,10 @@ export async function runDashboard(port: number, opts: { paused?: boolean; dev?:
 
     // Stop TUI if active
     if (tui) {
+      // Restore console.* before stopping the TUI so any log lines emitted
+      // during teardown (or by late-firing listeners) go to the real terminal
+      // instead of a ring buffer that's about to disappear.
+      logSink.releaseConsole();
       void tui.stop();
     }