* Add proto files for onboarding module
* Add generated proto bindings
* Define onboarding object
* Define the participants state in keeper
* Update genesis file to initialize and export module state to/from genesis
* Add msg to onboard participant
* Register command to enroll participant
* Add functionality to decode ethereum address from signature
* Add comments for messages and fields
* Fix lint errors in proto files
* Add message validation and events in msg_server
* Reuse crypto utils from go-nitro
* Sign entire eth_payload object
* Use google API for rpc method
* Regenerate proto bindings
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Co-authored-by: Prathamesh Musale <prathamesh.musale0@gmail.com>
