fixes #25475; incompatible types errors for array types with different index types

[ringabout]

fixes #25475

var x: array[0..1, int] = [0, 1]
var y: array[4'u..5'u, int] = [0, 3]

echo x == y

sigmatch treats array compatibility by element type + length, not by the index (range) type. Perhaps backend should do the same check

[Copilot]

Pull request overview

Adds a new consideration flag to signature hashing to normalize array index range handling, aiming to make array types hash more consistently (per #25475).

Changes:

• Introduces a new ConsiderFlag value: CoIgnoreRangeInarray.
• Updates hashType for tyRange to support hashing range length (instead of exact bounds) when the new flag is present.
• Updates hashType for tyArray to pass the new flag when hashing the array index type.

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[github-actions]

Thanks for your hard work on this PR!
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Hint: mm: orc; opt: speed; options: -d:release
189511 lines; 11.434s; 801.566MiB peakmem