[AURON #2153] Implement native function of map_from_entries

[weimingdiit]

Which issue does this PR close?

Closes #2153

Rationale for this change

map_from_entries(...) was not supported in Auron’s native execution path.
This PR extends native coverage for Spark map functions using the existing extension-function pattern already used for Spark-specific functions such as map_concat(...). The goal is to support this function natively while preserving Spark-compatible behavior.

What changes are included in this PR?

This PR:

• adds MapFromEntries conversion in NativeConverters
• passes Spark’s spark.sql.mapKeyDedupPolicy to the native implementation
• registers Spark_MapFromEntries in datafusion-ext-functions
• implements map_from_entries(...) in spark_map.rs
• handles Spark-compatible semantics for:
  • null input array -> null result
  • null entry inside the input array -> null result
  • null key -> error
  • duplicate keys -> error by default
  • duplicate keys with LAST_WIN -> last value wins
  • null values -> allowed
• adds Scala regression tests in AuronFunctionSuite
• adds Rust unit tests in spark_map.rs

Are there any user-facing changes?

Queries using map_from_entries(arrayOfEntries) can now run through Auron’s native extension-function path instead of falling back or remaining unsupported.

How was this patch tested?

CI.

[Copilot]

Pull request overview

Adds native execution-path support for Spark map_from_entries(...) via Auron’s extension-function mechanism, including Spark-compatible null/duplicate-key semantics and regression/unit test coverage.

Changes:

• Adds Spark-side conversion for MapFromEntries, passing spark.sql.mapKeyDedupPolicy into the native call.
• Registers and implements Spark_MapFromEntries in datafusion-ext-functions with Spark-compatible semantics.
• Adds Scala regression tests and Rust unit tests covering null handling and dedup policies.

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 2 comments.

File	Description
spark-extension/src/main/scala/org/apache/spark/sql/auron/NativeConverters.scala	Converts Spark MapFromEntries into Spark_MapFromEntries, passing dedup policy.
spark-extension-shims-spark/src/test/scala/org/apache/auron/AuronFunctionSuite.scala	Adds end-to-end Spark-vs-native regression tests for map_from_entries.
native-engine/datafusion-ext-functions/src/spark_map.rs	Implements native map_from_entries and adds Rust unit tests.
native-engine/datafusion-ext-functions/src/lib.rs	Registers Spark_MapFromEntries extension function.

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[slfan1989]

@weimingdiit Thanks for the contribution! Merged into the master.

[weimingdiit]

@slfan1989 Thanks for your review and merge