Prior to this, a proto file without a package declaration didn't
supported any operation as parser required that a package be present.
For missing package we now consider . as package
- [x] Hover
- [x] Prepare rename
- [x] Completion of enums and messages in current package
- [ ] ~Rename~ (Deferred to future)
- [x] Definition
- [ ] ~Workspace Symbols~ (No use as of now)
Handle extra operations to update inner state:
- [x] did_create_file
- [x] did_delete_file
- [x] did_rename_file
