[Java]:Add support for portable timestamp logical types (micros_instant, nanos_instant) in BeamCalcRel

[Suvrat1629]

Please add a meaningful description for your change here

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Addresses #36682
This PR adds full support for the standard portable timestamp logical types in Beam SQL:

• beam:logical_type:micros_instant:v1
• beam:logical_type:nanos_instant:v1

These types are now properly handled in BeamCalcRel across both directions:

• Beam Row → Calcite: Read as java.time.Instant using getLogicalTypeValue
• Calcite → Beam Row: Convert long millis → Instant for output

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[gemini-code-assist]

Summary of Changes

Hello @Suvrat1629, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request significantly enhances Beam SQL's data type compatibility by introducing comprehensive support for portable timestamp logical types, specifically micros_instant and nanos_instant. This allows for accurate and consistent processing of high-precision timestamp data across Beam Row and Calcite, improving the robustness of SQL operations involving time-based data. Additionally, it refines the handling of pass-through logical types to ensure their underlying base types are correctly managed during data transformations.

Highlights

• Portable Timestamp Logical Types Support: Added full support for beam:logical_type:micros_instant:v1 and beam:logical_type:nanos_instant:v1 in Beam SQL, enabling proper handling of these standard portable timestamp types.
• Beam Row to Calcite Conversion: Implemented the conversion of Calcite numeric values to java.time.Instant for micros_instant and nanos_instant when reading data from Beam Rows.
• Calcite to Beam Row Conversion: Implemented the conversion of java.time.Instant to epoch milliseconds for Calcite when writing data to Beam Rows for micros_instant and nanos_instant.
• PassThroughLogicalType Handling: Enhanced the handling of PassThroughLogicalType to correctly process underlying base types during conversions between Beam Row and Calcite, ensuring broader compatibility for logical types.

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[Suvrat1629]

/gemini review

[gemini-code-assist]

Code Review

This pull request adds support for micros_instant and nanos_instant logical types. The changes for this are mostly correct, but there is a critical bug in toBeamObject where it returns an org.joda.time.Instant instead of the required java.time.Instant.

Additionally, this PR includes a large, undocumented refactoring for handling PassThroughLogicalType. This refactoring is out of scope, implemented inconsistently between getBeamField and toCalciteValue, and introduces dead code. I've left comments suggesting to remove this refactoring and move it to a separate pull request to keep this change focused.

Once the bug is fixed and the unrelated refactoring is removed, this PR should be in good shape.

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[Suvrat1629]

/gemini review

[gemini-code-assist]

Code Review

This pull request adds support for the MicrosInstant and NanosInstant portable timestamp logical types in BeamCalcRel. The changes correctly handle conversions in both directions between Beam Rows and Calcite's representation, which is based on epoch milliseconds. This means that while the new types are supported, timestamp precision beyond milliseconds will be truncated when converting to Calcite. The implementation is consistent with how other timestamp types are handled in this class. I have one suggestion to refactor a duplicated condition to improve maintainability.