chore(engine): column expression evaluation for ambiguous column type look-ups

[ashwanthgoli]

What this PR does / why we need it:

This PR implements column expression evaluation with precedence rules for ambiguous column references.
(where ColumnRef type is ColumnTypeAmbiguous). When a column name exists in the schema with multiple column types (Generated, Metadata, Label), we now resolve values per-row using precedence order rather than selecting the first matching column entirely. It is still possible to look-up an exact column type by setting it in ColumnRef type

This approach retains type information throughout the query pipeline, which could be useful for log queries that may need to include this info in the query response.

Which issue(s) this PR fixes:
Fixes #

Special notes for your reviewer:

Checklist

• Reviewed the CONTRIBUTING.md guide (required)
• Documentation added
• Tests updated
• Title matches the required conventional commits format, see here
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