optional custom validation

[S1nus]

Overview

Sometimes, a rollup might want to customize the stateless validation behavior at runtime. For example, in a centralized sequencer scheme where the proposer pubkey is always known, this enables more efficient validation.

Checklist

• New and updated code has appropriate documentation
• New and updated code has new and/or updated testing
• Required CI checks are passing
• Visual proof for any user facing features like CLI or documentation updates
• Linked issues closed with keywords

[codecov-commenter]

Codecov Report

Merging #128 (ae7cd19) into main (a8ce731) will decrease coverage by 0.68%.
The diff coverage is 22.22%.

@@            Coverage Diff             @@
##             main     #128      +/-   ##
==========================================
- Coverage   65.01%   64.34%   -0.68%     
==========================================
  Files          39       39              
  Lines        3276     3290      +14     
==========================================
- Hits         2130     2117      -13     
- Misses        988     1011      +23     
- Partials      158      162       +4     

Files	Coverage Δ
p2p/exchange.go	84.27% <100.00%> (ø)
p2p/session.go	87.56% <28.57%> (-2.24%)	⬇️
p2p/subscriber.go	38.46% <0.00%> (-4.23%)	⬇️

... and 2 files with indirect coverage changes

[S1nus]

closing for now