feat: add detector for invalid memory-safe assembly annotations

[ep0chzer0]

Summary

Adds a new detector (incorrect-memory-safe) that identifies incorrect usage of the @solidity memory-safe-assembly annotation.

What it detects:

1. Regular comments instead of NatSpec - Annotations in // or /* */ comments are ignored by the compiler. Only NatSpec comments (/// or /** */) work.

2. Common typos - Detects misspellings like:

   • memory-sage-assembly (typo: 'sage' instead of 'safe')
   • memory safe assembly (spaces instead of hyphens)
   • memory_safe_assembly (underscores instead of hyphens)
   • And other common variations

Why this matters:

The @solidity memory-safe-assembly annotation tells the compiler that inline assembly code follows Solidity's memory model. When valid, the compiler can apply memory optimizations. However:

• Using regular comments (//) instead of NatSpec (///) means the annotation is silently ignored
• Developers may believe their code is optimized when it's not
• This leads to missed gas savings and false assumptions about code behavior

Example

// BAD: Regular comment - annotation is ignored
// @solidity memory-safe-assembly
assembly {
    result := mload(0x40)
}

// GOOD: NatSpec comment - annotation works
/// @solidity memory-safe-assembly
assembly {
    result := mload(0x40)
}

Test Coverage

• Test file with 4 invalid cases (regular comments, typos) and 3 valid cases
• Snapshot verifies all 4 issues are detected
• Valid cases (correct NatSpec, no annotation) are not flagged

Fixes #2780

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