test: add gas tests

[varunsrin]

Motivation

Require updating snapshots explicitly when gas usage for common functionality changes so that we are aware of regressions and improvements being introduced.

Change Summary

Added snapshot tests for common functions in Bundler, StorageRent

Merge Checklist

• [x] The PR title adheres to the conventional commits standard
• [x] The PR has been tagged with change type label(s) (i.e. documentation, feature, bugfix, or chore)
• [x] The PR's changes adhere to all the requirements in the contribution guidelines
• [x] This PR does not require changes to the Farcaster protocol

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PR-Codex overview

Focus of the PR:

This PR focuses on adding gas usage tests for the BundleRegistry and StorageRent contracts.

Detailed summary:

• Added gas usage tests for BundleRegistry's register, trustedRegister, and trustedBatchRegister functions.
• Added gas usage tests for StorageRent's rent, batchRent, credit, batchCredit, and continuousCredit functions.

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[github-actions[bot]]

Coverage after merging varunsrin/gas-price-tests into main will be

96.91%

Coverage Report

File	Stmts	Branches	Funcs	Lines	Uncovered Lines
src
Bundler.sol	100%	100%	100%	100%
FnameResolver.sol	96.30%	75%	100%	100%	121
IdRegistry.sol	97.30%	100%	92.31%	97.44%	315
StorageRent.sol	98.80%	98.33%	100%	98.86%	495, 497
src/lib
TransferHelper.sol	0%	0%	0%	0%	15, 15, 15, 25–26, 26, 26