fix(parser): keep parenthesized multi-param lambda as first function arg

[ivanclarksoft]

Summary

array_map((x,y,z) -> x + y, …) incorrectly kept only the parameter list (x, y, z) as the first argument. Tokens for -> body were consumed, then discarded by an unconditional reassignment after ParenthesedExpressionList().

Changes

• In PrimaryExpression(), make the lambda branch and the plain-list assignment mutually exclusive.
• Add regression test testLambdaFirstArgumentIssue2195.

Test plan

• mvn -Dtest=LambdaExpressionTest test

Fixes #2195

[manticore-projects]

Thank you for your work and effort. Please run './gradlew spotlessApply' to fix all format violations and ./gradlew check before committing.

[ivanclarksoft]

Thanks for the review — I've run formatting for the Spotless violation in LambdaExpressionTest.java (long sqlStr wrap) and pushed to this branch. ./gradlew spotlessApply / ./gradlew check are what CI will re-run on the update; please take another look when convenient.

[manticore-projects]

Thank you for your work and effort!