feat: minor lambda perf improvements (#21896)

## Which issue does this PR close?

<!--
We generally require a GitHub issue to be filed for all bug fixes and
enhancements and this helps us generate change logs for our releases.
You can link an issue to this PR using the GitHub syntax. For example
`Closes #123` indicates that this PR will close issue #123.
-->

- Closes #.

Followup on
#21679 (comment)

## Rationale for this change

<!--
Why are you proposing this change? If this is already explained clearly
in the issue then this section is not needed.
Explaining clearly why changes are proposed helps reviewers understand
your changes and offer better suggestions for fixes.
-->

## What changes are included in this PR?

<!--
There is no need to duplicate the description in the issue here but it
is sometimes worth providing a summary of the individual changes in this
PR.
-->

## Are these changes tested?

<!--
We typically require tests for all PRs in order to:
1. Prevent the code from being accidentally broken by subsequent changes
2. Serve as another way to document the expected behavior of the code

If tests are not included in your PR, please explain why (for example,
are they covered by existing tests)?
-->

## Are there any user-facing changes?

<!--
If there are user-facing changes then we may require documentation to be
updated before approving the PR.
-->

<!--
If there are any breaking changes to public APIs, please add the `api
change` label.
-->

---------

Co-authored-by: Raz Luvaton <16746759+rluvaton@users.noreply.github.com>

Author: comphead

datafusion/expr/src/higher_order_function.rs

@@ -21,6 +21,7 @@ use crate::expr::schema_name_from_exprs_comma_separated_without_space;
 use crate::{ColumnarValue, Documentation, Expr};
 use arrow::array::{ArrayRef, RecordBatch};
 use arrow::datatypes::{DataType, FieldRef, Schema};
+use arrow_schema::SchemaRef;
 use datafusion_common::config::ConfigOptions;
 use datafusion_common::{Result, ScalarValue, not_impl_err};
 use datafusion_expr_common::dyn_eq::{DynEq, DynHash};
@@ -218,11 +219,21 @@ pub struct LambdaArgument {
     /// For example, for `array_transform([2], v -> -v)`,
     /// this will be the physical expression of `-v`
     body: Arc<dyn PhysicalExpr>,
+    /// Cached schema built from `params`. Reused across every `evaluate` call
+    /// (and across every nested-list iteration when the lambda is called once
+    /// per outer sublist), avoiding the per-call `Schema::new` build that
+    /// includes constructing the internal name -> index map.
+    schema: SchemaRef,
 }
 
 impl LambdaArgument {
     pub fn new(params: Vec<FieldRef>, body: Arc<dyn PhysicalExpr>) -> Self {
-        Self { params, body }
+        let schema = Arc::new(Schema::new(params.clone()));
+        Self {
+            params,
+            body,
+            schema,
+        }
     }
 
     /// Evaluate this lambda
@@ -238,9 +249,7 @@ impl LambdaArgument {
             .map(|arg| arg())
             .collect::<Result<_>>()?;
 
-        let schema = Arc::new(Schema::new(self.params.clone()));
-
-        let batch = RecordBatch::try_new(schema, columns)?;
+        let batch = RecordBatch::try_new(Arc::clone(&self.schema), columns)?;
 
         self.body.evaluate(&batch)
     }