Create LedgerPreprocessHook to reformat EIP-712 payloads

[0a1c]

Closes: #XXX

Description

This PR implements the Ledger EIP-712 preprocessing required to format EIP-712 transactions for verification, by including the signature information in a Web3Tx extension, setting the signature in the tx body to be blank, and setting the SignMode to be LEGACY_AMINO for Ledger-signed transactions.

This preprocessing will be performed on each transaction submitted via the CLI; however, all non-Ledger interactions should short-circuit.

This must be modified (if not completely removed) when an Evmos Ledger app becomes available, as that would not benefit from this preprocessing.

Tests

Test Coverage:

• Basic functionality on populated and unpopulated transactions
• Short-circuit on non-Ledger transactions
• Error-checking functionality on blank transactions & invalid chain id

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For contributor use:

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• Code follows the module structure standards.
• Wrote unit and integration tests
• Updated relevant documentation (docs/) or specification (x/<module>/spec/)
• Added relevant godoc comments.
• Added a relevant changelog entry to the Unreleased section in CHANGELOG.md
• Re-reviewed Files changed in the Github PR explorer

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For admin use:

• Added appropriate labels to PR (ex. WIP, R4R, docs, etc)
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[lgtm-com]

This pull request introduces 1 alert when merging d897959 into f11bc35 - view on LGTM.com

new alerts:

• 1 for Useless assignment to local variable

[lgtm-com]

This pull request introduces 1 alert when merging 6dea312 into c9fe1d1 - view on LGTM.com

new alerts:

• 1 for Useless assignment to local variable

[codecov]

Codecov Report

Merging #1277 (ba87b4d) into main (14e2f8d) will decrease coverage by 1.74%.
The diff coverage is 67.85%.

❗ Current head ba87b4d differs from pull request most recent head 7b66432. Consider uploading reports for the commit 7b66432 to get more accurate results

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1277      +/-   ##
==========================================
- Coverage   56.53%   54.78%   -1.75%     
==========================================
  Files         105      107       +2     
  Lines        9609     9984     +375     
==========================================
+ Hits         5432     5470      +38     
- Misses       3912     4243     +331     
- Partials      265      271       +6     

Impacted Files	Coverage Δ
ethereum/eip712/preprocess.go	67.85% <67.85%> (ø)
ethereum/eip712/eip712.go	0.00% <0.00%> (ø)

[lgtm-com]

This pull request introduces 1 alert when merging ac17f58 into c9fe1d1 - view on LGTM.com

new alerts:

• 1 for Useless assignment to local variable

[lgtm-com]

This pull request introduces 1 alert when merging bbcec73 into 45fdcaf - view on LGTM.com

new alerts:

• 1 for Useless assignment to local variable

[danburck]

@austinchandra LGTM, left some comments on how to approve the comments.

[fedekunze]

ACK, left a comment about supporting multisigs. Can you add a feature changelog entry?