Migrating front protobuf encode/decode to ts-proto lib

The ts-proto lib has the huge advantage of producing code the "Typescript" way and not the "Java" way.
In particular, for "oneof" types in protobuf, it is generating "ADT" that can be used to check if we forgot or not to deal with a type.

.github/workflows/continuous_integration.yml

@@ -39,7 +39,7 @@ jobs:
         working-directory: "messages"
 
       - name: "Build proto messages"
-        run: yarn run proto && yarn run copy-to-front && yarn run json-copy-to-front
+        run: yarn run ts-proto && yarn run copy-to-front-ts-proto && yarn run json-copy-to-front
         working-directory: "messages"
 
       - name: "Create index.html"