feat: (hopefully) better intermediate representation

ref: N25B-376

src/control_backend/schemas/program.py

@@ -1,4 +1,5 @@
 from enum import Enum
+from typing import Literal
 
 from pydantic import UUID4, BaseModel
 
@@ -133,9 +134,17 @@ class SpeechAction(ProgramElement):
     text: str
 
 
-# TODO: gestures
-class Gesture(Enum):
-    RAISE_HAND = "RAISE_HAND"
+class Gesture(BaseModel):
+    """
+    Represents a gesture to be performed. Can be either a single gesture,
+    or a random gesture from a category (tag).
+
+    :ivar type: The type of the gesture, "tag" or "single".
+    :ivar name: The name of the single gesture or tag.
+    """
+
+    type: Literal["tag", "single"]
+    name: str
 
 
 class GestureAction(ProgramElement):