report per-ticker R:R scanner progress (sidebar stuck at 0%)

scan_rr set the total then called scan_all_tickers as one opaque await, so the
runtime snapshot's processed count stayed 0 until the whole scan finished and
jumped straight to 100%. scan_all_tickers now takes an optional progress_callback
invoked per ticker; the scheduler wires it to _runtime_progress so the sidebar's
live indicator advances as tickers are scanned.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

app/scheduler.py

@@ -654,9 +654,15 @@ async def scan_rr() -> None:
             total = len(symbols)
             _runtime_progress(job_name, processed=0, total=total)
 
+            def _on_progress(done: int, count: int, symbol: str) -> None:
+                _runtime_progress(
+                    job_name, processed=done, total=count, current_ticker=symbol or None
+                )
+
             try:
                 setups = await scan_all_tickers(
                     db, rr_threshold=settings.default_rr_threshold,
+                    progress_callback=_on_progress,
                 )
                 processed = total or 0
                 _runtime_finish(job_name, "completed", processed=processed, total=total, message=f"Found {len(setups)} setups")