Improve Linter

[clement-ux]

Description

Forge provides a new linter based on Solar, a Rust based solidity compiler.
This PR aims to discuss about should we use it or not?
Note: we can choose to only run it on contracts, not on script or test.

Pros

• We could have a standardized approach for variable naming (this is the biggest point).
• We could enforce it when creating a PR, to ensure code is standardized.
• It could help us to fix issue before they appear: like unsafe-typecast (this is the only case I encountered):

warning[unsafe-typecast]: typecasts that can truncate values should be checked
   --> src/contracts/AbstractARM.sol:594:33
    |
594 |         uint40 claimTimestamp = uint40(block.timestamp + claimDelay);
    |                                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |

Cons

• Less flexibility on the naming (but this help to standardize the code).
• A lot of false alarm like this one, but we can easily remove it with inline comment though.

warning[erc20-unchecked-transfer]: ERC20 'transfer' and 'transferFrom' calls should check the return value
   --> src/contracts/AbstractARM.sol:651:9
    |
651 |         IERC20(liquidityAsset).transfer(msg.sender, assets);
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |

How to try

Ensure you use last Foundry version + build

foundryup
forge b

Try linter

forge l

Docs

Forge-lint rules — by severity

Severity	Lint ID / Rule	What it checks / Risk
High	incorrect-shift	Bit-shift where a literal is shifted by a variable — likely a wrong operand order / logic bug.
	unchecked-call	Low-level calls (.call(), .delegatecall(), .staticcall()) without checking success return — risk of silent failure / security issue.
	erc20-unchecked-transfer	ERC-20 transfer / transferFrom calls ignoring the boolean return — transfers might silently fail.
Medium	divide-before-multiply	Integer arithmetic doing division before multiplication in the same expression — may cause precision loss (due to truncation).
	unsafe-typecast	Unsafe type casts (e.g. large → smaller integer) — risk of data loss or unexpected behaviour.
Info / Style	pascal-case-struct	Enforces PascalCase naming for structs — style / readability.
	mixed-case-function	Enforces mixedCase (camelCase) for function names — style / readability.
	mixed-case-variable	Enforces mixedCase naming for mutable variables — style / readability.
	screaming-snake-case-const	Enforces SCREAMING_SNAKE_CASE naming for constant variables — style / readability.
	screaming-snake-case-immutable	Enforces SCREAMING_SNAKE_CASE naming for immutable variables — style / readability.
	unused-import	Warns about imports that are never used — avoids unnecessary imports / clutter.
	unaliased-plain-import	Warns when using plain imports without alias — encourages clearer import naming / avoids name conflicts.
Gas optimizations	asm-keccak256	Suggests using inline-assembly keccak256 when appropriate — may reduce gas usage vs high-level call.
Code-size (bytecode)	unwrapped-modifier-logic	Flags modifiers containing logic outside the _ placeholder — such logic is duplicated per function, increasing contract size.

• Here is the list of all lints that are supported, ranked by severity: https://getfoundry.sh/forge/linting/#erc20-unchecked-transfer
• Here is the global documentation: https://getfoundry.sh/config/reference/linter/#linter-configuration