fix(run_pipeline_mode): set up PerformanceMonitor for FPS tracking in HUD

engine/app.py

@@ -966,7 +966,7 @@ def run_pipeline_mode(preset_name: str = "demo"):
     """Run using the new unified pipeline architecture."""
     import effects_plugins
     from engine.display import DisplayRegistry
-    from engine.effects import get_registry
+    from engine.effects import PerformanceMonitor, get_registry, set_monitor
     from engine.fetch import fetch_all, fetch_poetry, load_cache
     from engine.pipeline import (
         Pipeline,
@@ -985,6 +985,9 @@ def run_pipeline_mode(preset_name: str = "demo"):
 
     effects_plugins.discover_plugins()
 
+    monitor = PerformanceMonitor()
+    set_monitor(monitor)
+
     preset = get_preset(preset_name)
     if not preset:
         print(f"  \033[38;5;196mUnknown preset: {preset_name}\033[0m")