* remove RLN proof generation from lightpush server to client
* set timestamp before generating lightpush msg proof
* Add explicit error message for checkAndGenerateRLNProof and oneline for ensureTimestampSet
* Change ensureTimestampSet from func to proc
* Add rln validator to mountRlnRelay
* remove requirement for relay when mounting RLN
* Rename mountRlnRelay to setRlnValidator
* Clean up setRlnValidator: update log wording, drop unused let bindings
* Fix botched setRlnValidator callsites from rename
* Drop obsolete test: setRlnValidator no longer requires relay
* Remove unused code in test utils
* remove unused import for rln
* move rln specific procs and types
* Renaming and restructuring RLN module
* Rename waku_rln_relay to waku_rln
* rename rln-relay types to rln
* Fix linting
* update logScope topics to match new rln module name
* Rename waku_rln module to rln
* Rename WakuRln type to Rln, rename FFI raw type to RlnRaw to avoid collision
* Apply nph formatting
* Rename local rlnRelay to rln in mountRlnRelay