add basic support for mypy type checking

scripts/process_android_emulator_protos.sh

@@ -0,0 +1,27 @@
+# Invoke this script with an argument pointing to where the Android emulator .proto files are.
+# The .proto files should be slightly modified from their original version (as distributed with
+# the Android emulator):
+# --> Remove unused types/methods from emulated_bluetooth.proto
+
+PROTOC_OUT=bumble/transport
+LICENSE_FILE_INPUT=bumble/transport/android_emulator.py
+
+proto_files=(emulated_bluetooth.proto emulated_bluetooth_vhci.proto emulated_bluetooth_packets.proto)
+for proto_file in "${proto_files[@]}"
+do
+    python -m grpc_tools.protoc -I$1 --proto_path=bumble/transport --python_out=$PROTOC_OUT --pyi_out=$PROTOC_OUT --grpc_python_out=$PROTOC_OUT $1/$proto_file
+done
+
+python_files=(emulated_bluetooth_pb2.py emulated_bluetooth_pb2_grpc.py emulated_bluetooth_packets_pb2.py emulated_bluetooth_packets_pb2_grpc.py emulated_bluetooth_vhci_pb2_grpc.py emulated_bluetooth_vhci_pb2.py)
+for python_file in "${python_files[@]}"
+do
+    sed -i '' 's/^import .*_pb2 as/from . &/' $PROTOC_OUT/$python_file
+done
+
+stub_files=(emulated_bluetooth_pb2.pyi emulated_bluetooth_packets_pb2.pyi emulated_bluetooth_vhci_pb2.pyi)
+for source_file in "${python_files[@]}" "${stub_files[@]}"
+do
+    head -14 $LICENSE_FILE_INPUT > $PROTOC_OUT/${source_file}.lic
+    cat $PROTOC_OUT/$source_file >> $PROTOC_OUT/${source_file}.lic
+    mv $PROTOC_OUT/${source_file}.lic $PROTOC_OUT/$source_file
+done