Animation: Sensible frame range for motion paths

Motion paths can now be initialised to more sensible frame ranges,
rather than simply 1-250:

    - Scene Frame Range
    - Selected Keyframes
    - All Keyframes

Reviewed By: sybren, looch, dfelinto, pablico

Maniphest Tasks: T93047

Differential Revision: https://developer.blender.org/D13687

source/blender/editors/include/ED_anim_api.h

@@ -1096,6 +1096,15 @@ void animviz_calc_motionpaths(struct Depsgraph *depsgraph,
                               eAnimvizCalcRange range,
                               bool restore);
 
+/**
+ * Update motion path computation range (in ob.avs or armature.avs) from user choice in
+ *  ob.avs.path_range or arm.avs.path_range, depending on active user mode.
+ *
+ * @param ob: Object to compute range for (must be provided)
+ * @param scene: Used when scene range is choosen
+ */
+void animviz_motionpath_compute_range(struct Object *ob, struct Scene *scene);
+
 /**
  * Get list of motion paths to be baked for the given object.
  * - assumes the given list is ready to be used.