[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/generate_bazel_files.py

@@ -2,18 +2,24 @@
 import sys
 import tomli
 
-def main():
-    toml_filename = "robotpyExamples/examples.toml"
-    output_file = "robotpyExamples/example_projects.bzl"
+def load_project_names(toml_filename, project_type):
     
     with open(toml_filename, "rb") as f:
         data = tomli.load(f)
 
-    contents = "PROJECTS = [\n"
+    contents = f"{project_type.upper()}_PROJECTS = [\n"
     for test_folder in data["tests"]["base"]:
-        contents += f'    "{test_folder}",\n'
+        contents += f'    "{project_type}s/{test_folder}",\n'
     contents += "]\n"
 
+    return contents
+
+def main():
+    output_file = "robotpyExamples/example_projects.bzl"
+
+    contents = load_project_names("robotpyExamples/examples/examples.toml", "example")
+    contents += load_project_names("robotpyExamples/snippets/snippets.toml", "snippet")
+
     if len(sys.argv) == 2:
         output_file = sys.argv[1]