Fix: Apply case-sensitive filter in uniqueness validation

[Gitesh307]

Fixes #4058

This PR addresses the case sensitivity discrepancy between frontend and backend uniqueness rules. Previously, the frontend enforced case-sensitive uniqueness, but the backend validation raised exceptions due to case-insensitive checks. The implementation has been updated so that backend uniqueness validation now uses case-sensitive matching (BINARY comparison) on string fields, while preserving the original behavior for related lookups and non-string fields. This brings the backend into alignment with the frontend, ensuring consistent validation across the application.

Checklist

• Self-review the PR after opening it to make sure the changes look good and
  self-explanatory (or properly documented)
• Add relevant issue to release milestone

Testing instructions

• Define a uniqueness rule on a text field (e.g., remarks) in Uniqueness Rules.
• Create a record (e.g., Accession) with a text value, e.g., abc.
• Create another record with the same text in different case, e.g., aBc.
• Verify: the record is created successfully without any uniqueness error.
• Verify that unique fields (e.g., username) correctly block case-sensitive duplicates on the frontend by showing a validation warning instead of allowing submission and throwing a backend BusinessRuleException.

[emenslin]

• Define a uniqueness rule on a text field (e.g., remarks) in Uniqueness Rules.
• Create a record (e.g., Accession) with a text value, e.g., abc.
• Create another record with the same text in different case, e.g., aBc.
• Verify: the record is created successfully without any uniqueness error.

Looks good, I tried with a few different text fields and I didn't run into any issues.

[lexiclevenger]

• Define a uniqueness rule on a text field (e.g., remarks) in Uniqueness Rules.
• Create a record (e.g., Accession) with a text value, e.g., abc.
• Create another record with the same text in different case, e.g., aBc.
• Verify: the record is created successfully without any uniqueness error.
• Verify that unique fields (e.g., username) correctly block case-sensitive duplicates on the frontend by showing a validation warning instead of allowing submission and throwing a backend BusinessRuleException.

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Looks good! No error occurs when unique fields have the same text with different cases

[melton-jason]

Nice work! 👏 🚀

Nothing major in my comments, primarily just refactoring/code maintainability suggestions.

[melton-jason]

Nice work!