Evaluate remeda for runtime checks

[crankshift]

Summary

Evaluate whether remeda improves clarity for runtime checks currently written with raw manual JavaScript checks.

Context

Some validation code may be easier to read with a small utility library, but native JavaScript should remain where it is clearer. This task is explicitly an evaluation plus selective replacement, not a blanket migration.

Acceptance Criteria

• Existing raw runtime checks such as typeof, Number.isInteger, and similar patterns are inventoried.
• remeda is adopted only if it materially improves clarity in concrete call sites.
• Native JavaScript checks remain where they are clearer than remeda equivalents.
• Tests are added or updated for behavior touched by any replacements.
• Normal verification passes after any changes.

Notes

Keep dependency and bundle impact in mind. It is acceptable for the outcome to be “do not adopt” if the code is clearer without remeda.