feat(patterns): align manual and auto behaviour

Unify manual/auto timing semantics for key patterns, add preset background support, and improve runtime observability while keeping the driver responsive under beat-triggered selects.

Co-authored-by: Cursor <cursoragent@cursor.com>

src/preset.py

@@ -12,6 +12,7 @@ class Preset:
         self.n4 = 0
         self.n5 = 0
         self.n6 = 0
+        self.bg = (0, 0, 0)
 
         # Override defaults with provided data
         self.edit(data)
@@ -25,9 +26,10 @@ class Preset:
             "delay": "d",
             "brightness": "b",
             "auto": "a",
+            "background": "bg",
         }
         int_fields = {"d", "b", "n1", "n2", "n3", "n4", "n5", "n6"}
-        allowed_fields = {"p", "c", "d", "b", "a", "n1", "n2", "n3", "n4", "n5", "n6"}
+        allowed_fields = {"p", "c", "d", "b", "a", "bg", "n1", "n2", "n3", "n4", "n5", "n6"}
         for key, value in data.items():
             key = aliases.get(key, key)
             if key not in allowed_fields:
@@ -56,6 +58,21 @@ class Preset:
             elif key == "c":
                 if isinstance(value, (list, tuple)):
                     self.c = value
+            elif key == "bg":
+                if isinstance(value, str) and value.startswith("#") and len(value) == 7:
+                    try:
+                        self.bg = (
+                            int(value[1:3], 16),
+                            int(value[3:5], 16),
+                            int(value[5:7], 16),
+                        )
+                    except (TypeError, ValueError):
+                        continue
+                elif isinstance(value, (list, tuple)) and len(value) == 3:
+                    try:
+                        self.bg = tuple(max(0, min(255, int(x))) for x in value)
+                    except (TypeError, ValueError):
+                        continue
             else:
                 setattr(self, key, value)
         return True
@@ -101,6 +118,12 @@ class Preset:
         self.a = value
 
     def background_or(self, colors=None, default=(0, 0, 0)):
+        bg = getattr(self, "bg", None)
+        if isinstance(bg, (list, tuple)) and len(bg) == 3:
+            try:
+                return tuple(max(0, min(255, int(x))) for x in bg)
+            except (TypeError, ValueError):
+                return default
         return default
 
     def to_dict(self):
@@ -110,6 +133,7 @@ class Preset:
             "b": self.b,
             "c": self.c,
             "a": self.a,
+            "bg": self.bg,
             "n1": self.n1,
             "n2": self.n2,
             "n3": self.n3,