[robotpy][examples] Split examples and snippets (#8944)

This also updates the bazel scripts to behave more like the C++ and Java
examples, and updates the copybara scripts to be able to sync up
`mostrobotpy`

robotpyExamples/examples/DriveDistanceOffboard/constants.py

@@ -0,0 +1,40 @@
+#
+# Copyright (c) FIRST and other WPILib contributors.
+# Open Source Software; you can modify and/or share it under the terms of
+# the WPILib BSD license file in the root directory of this project.
+#
+
+"""
+A place for the constant values in the code that may be used in more than one place.
+This offers a convenient resources to teams who need to make both quick and universal
+changes.
+"""
+
+import math
+
+
+class DriveConstants:
+    kDt = 0.02
+    kLeftMotor1Port = 0
+    kLeftMotor2Port = 1
+    kRightMotor1Port = 2
+    kRightMotor2Port = 3
+
+    """
+    These are example values only - DO NOT USE THESE FOR YOUR OWN ROBOT!
+    These characterization values MUST be determined either experimentally or theoretically
+    for *your* robot's drive.
+    The SysId tool provides a convenient method for obtaining these values for your robot.
+    """
+    ks = 1.0  # V
+    kv = 0.8  # V/(m/s)
+    ka = 0.15  # V/(m/s²)
+
+    kp = 1.0
+
+    kMaxVelocity = 3.0  # m/s
+    kMaxAcceleration = 3.0  # m/s²
+
+
+class OIConstants:
+    kDriverControllerPort = 0