fix: solidity coding style

[NicolasRampoldi]

Description

• Adds solhint linter to the CI. To run solhint locally, go to contracts, run npm install and then npm run lint:sol. The CI will run the linter but won't stop the user from pushing to main, it just lists the warnings.
• Fixes most linter warnings, the ones left don't seem relevant.
• The three rules added were taken from https://github.com/lambdaclass/era-contracts/blob/main/.solhint.json and it made sense to add them to this repo too.
• Add make lint_contracts to makefile

To Test

• Try deploying and test normal flow.
• Make some errors on purpose to see if the refactoring of requires to custom errors works properly.

[github-actions]

Changes to gas cost

Generated at commit: bc78cc93f7fa31d0ab2ff3a1fbc79cadd9a20962, compared to commit: 19e76e0f07a383afcba000953afed50d8ae10964

🧾 Summary (10% most significant diffs)

Contract	Method	Avg (+/-)	%
AlignedLayerServiceManager	createNewTask	-27 ✅	-0.05%

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Full diff report 👇

Contract	Deployment Cost (+/-)	Method	Min (+/-)	%	Avg (+/-)	%	Median (+/-)	%	Max (+/-)	%	# Calls (+/-)
AlignedLayerServiceManager	4,359,036 (-46,214)	createNewTask	51,138 (0)	0.00%	51,319 (-27)	-0.05%	51,234 (-12)	-0.02%	51,936 (0)	0.00%	256 (0)

[uri-99]

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[uri-99]

Everything seems to be working fine, and read it over for quite some time, but we should talk about this PR because it is pretty big and potentially dangerous.

I used to like a lot the require statements, but custom errors are pretty powerful, mainly because of accepting parameters. More info on this: https://soliditylang.org/blog/2021/04/21/custom-errors/

It looks like it should be compatible with an upgrade, with no need of changing the GAP, but this should be tested more in detail just in case.

Also, should errors be declared in the Interface? While we're at it, Events could also be declared in the Interface.

Also I believe this PR should require at least 3 or even 4 approves.

Finally, a make target to run solhint should come in pretty handy.

[taturosati]

Code lgtm, worked in my machine