FFI: plumb with_updated_config for FFI_ScalarUDF

[Amogh-2404]

Which issue does this close?

Part of #22330.

Rationale for this change

FFI_ScalarUDF doesn't plumb with_updated_config, so a provider that overrides it has the override silently dropped across the FFI boundary — the consumer falls back to the trait default (None). Continues the method-coverage work started with placement (#22608).

What changes are included in this PR?

• Adds a with_updated_config fn pointer to FFI_ScalarUDF plus the wrapper and forwarding on both sides. Config crosses in via the existing FFI_ConfigOptions; the reconfigured UDF comes back as FFI_Option<FFI_ScalarUDF>.
• A forced-foreign unit test and a cross-cdylib integration test, both asserting the override survives the boundary.

Adding the field changes the #[repr(C)] layout, so this is an ABI change.

Are these changes tested?

Yes — cargo test -p datafusion-ffi --features integration-tests.

Are there any user-facing changes?

ABI change for FFI consumers (recompile required). No SQL-level changes.

[github-actions]

Thank you for opening this pull request!

Reviewer note: cargo-semver-checks reported the current version number is not SemVer-compatible with the changes in this pull request (compared against the base branch).

Details

     Cloning apache/main
    Building datafusion-ffi v53.1.0 (current)
       Built [  64.006s] (current)
     Parsing datafusion-ffi v53.1.0 (current)
      Parsed [   0.065s] (current)
    Building datafusion-ffi v53.1.0 (baseline)
       Built [  60.087s] (baseline)
     Parsing datafusion-ffi v53.1.0 (baseline)
      Parsed [   0.064s] (baseline)
    Checking datafusion-ffi v53.1.0 -> v53.1.0 (no change; assume patch)
     Checked [   0.359s] 223 checks: 221 pass, 1 fail, 1 warn, 30 skip

--- failure constructible_struct_adds_field: externally-constructible struct adds field ---

Description:
A pub struct constructible with a struct literal has a new pub field. Existing struct literals must be updated to include the new field.
        ref: https://doc.rust-lang.org/reference/expressions/struct-expr.html
       impl: https://github.com/obi1kenobi/cargo-semver-checks/tree/v0.48.0/src/lints/constructible_struct_adds_field.ron

Failed in:
  field FFI_ScalarUDF.with_updated_config in /home/runner/work/datafusion/datafusion/datafusion/ffi/src/udf/mod.rs:99
  field ForeignLibraryModule.create_with_config_udf in /home/runner/work/datafusion/datafusion/datafusion/ffi/src/tests/mod.rs:94

--- warning repr_c_plain_struct_fields_reordered: struct fields reordered in repr(C) struct ---

Description:
A public repr(C) struct had its fields reordered. This can change the struct's memory layout, possibly breaking FFI use cases that depend on field position and order.
        ref: https://doc.rust-lang.org/reference/type-layout.html#reprc-structs
       impl: https://github.com/obi1kenobi/cargo-semver-checks/tree/v0.48.0/src/lints/repr_c_plain_struct_fields_reordered.ron

Failed in:
  FFI_ScalarUDF.clone moved from position 8 to 9, in /home/runner/work/datafusion/datafusion/datafusion/ffi/src/udf/mod.rs:107
  FFI_ScalarUDF.release moved from position 9 to 10, in /home/runner/work/datafusion/datafusion/datafusion/ffi/src/udf/mod.rs:110
  FFI_ScalarUDF.private_data moved from position 10 to 11, in /home/runner/work/datafusion/datafusion/datafusion/ffi/src/udf/mod.rs:114
  FFI_ScalarUDF.library_marker_id moved from position 11 to 12, in /home/runner/work/datafusion/datafusion/datafusion/ffi/src/udf/mod.rs:119
  ForeignLibraryModule.create_table_function moved from position 8 to 9, in /home/runner/work/datafusion/datafusion/datafusion/ffi/src/tests/mod.rs:96
  ForeignLibraryModule.create_sum_udaf moved from position 9 to 10, in /home/runner/work/datafusion/datafusion/datafusion/ffi/src/tests/mod.rs:100
  ForeignLibraryModule.create_stddev_udaf moved from position 10 to 11, in /home/runner/work/datafusion/datafusion/datafusion/ffi/src/tests/mod.rs:103
  ForeignLibraryModule.create_rank_udwf moved from position 11 to 12, in /home/runner/work/datafusion/datafusion/datafusion/ffi/src/tests/mod.rs:105
  ForeignLibraryModule.create_extension_options moved from position 12 to 13, in /home/runner/work/datafusion/datafusion/datafusion/ffi/src/tests/mod.rs:108
  ForeignLibraryModule.create_empty_exec moved from position 13 to 14, in /home/runner/work/datafusion/datafusion/datafusion/ffi/src/tests/mod.rs:110
  ForeignLibraryModule.create_exec_with_statistics moved from position 14 to 15, in /home/runner/work/datafusion/datafusion/datafusion/ffi/src/tests/mod.rs:112
  ForeignLibraryModule.create_table_with_statistics moved from position 15 to 16, in /home/runner/work/datafusion/datafusion/datafusion/ffi/src/tests/mod.rs:114
  ForeignLibraryModule.create_physical_optimizer_rule moved from position 16 to 17, in /home/runner/work/datafusion/datafusion/datafusion/ffi/src/tests/mod.rs:117
  ForeignLibraryModule.create_context_aware_optimizer_rule moved from position 17 to 18, in /home/runner/work/datafusion/datafusion/datafusion/ffi/src/tests/mod.rs:119
  ForeignLibraryModule.version moved from position 18 to 19, in /home/runner/work/datafusion/datafusion/datafusion/ffi/src/tests/mod.rs:121

     Summary semver requires new major version: 1 major and 0 minor checks failed
     Warning produced 1 major and 0 minor level warnings
    Finished [ 127.090s] datafusion-ffi