[Feat] Automate smart contract docgen and PR branch creation into Linea docs repo

[kyzooghost]

This PR implements issue(s) #4031

Checklist

• I wrote new tests for my new core changes.
• I have successfully ran tests, style checker and build against my new changes locally.
• I have informed the team of any breaking changes if there are any.

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 68.17%. Comparing base (4e93fa3) to head (a43d761).
Report is 19 commits behind head on main.

Additional details and impacted files

@@             Coverage Diff              @@
##               main     #446      +/-   ##
============================================
- Coverage     70.17%   68.17%   -2.01%     
- Complexity     1070     1125      +55     
============================================
  Files           306      319      +13     
  Lines         12337    12789     +452     
  Branches       1179     1275      +96     
============================================
+ Hits           8658     8719      +61     
- Misses         3200     3542     +342     
- Partials        479      528      +49     

Flag	Coverage Δ
hardhat	98.59% <ø> (-0.11%)	⬇️
kotlin	65.80% <ø> (-2.07%)	⬇️

Files with missing lines	Coverage Δ
contracts/contracts/lib/SparseMerkleProof.sol	100.00% <ø> (ø)

... and 46 files with indirect coverage changes