FLINK-XXXXX: add GROUP BY <int literal>, GROUP BY ALL, ORDER BY ALL support

[tisyabhatia]

What is the purpose of the change

This pull request adds initial support for GROUP BY ALL in Flink SQL.

The change introduces parser and validator support for GROUP BY ALL, adds planner handling behind a configuration flag, and includes parser and batch planner test coverage. The implementation is intentionally scoped and does not attempt to support all related variants yet.

This work is also backed by an internal design doc and FLIP draft.

Brief change log

• Add parser support for GROUP BY ALL
• Add a SqlGroupByAllOperator representation for parsing and validation
• Extend validator logic to recognize and rewrite GROUP BY ALL
• Add a table config option / feature flag for the behavior
• Add parser tests for GROUP BY ALL
• Add batch planner tests for GROUP BY ALL

Verifying this change

This change added tests and can be verified as follows:

• Added parser coverage in FlinkSqlParserImplTest
• Added batch planner coverage in GroupByAllTest
• Manually verified the parser / validator / planner flow for GROUP BY ALL
• Verified the change is gated by the corresponding table config option

Does this pull request potentially affect one of the following parts:

• Dependencies (does it add or upgrade a dependency): no
• The public API, i.e., is any changed class annotated with @Public(Evolving): no
• The serializers: no
• The runtime per-record code paths (performance sensitive): no
• Anything that affects deployment or recovery: JobManager (and its components), Checkpointing, Kubernetes/Yarn, ZooKeeper: no
• The S3 file system connector: no

Documentation

• Does this pull request introduce a new feature? yes
• If yes, how is the feature documented? not documented in this PR yet; design details are currently captured in the internal design doc and FLIP draft

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Was generative AI tooling used to co-author this PR?

• Yes

Generated-by: Glean

[flinkbot]

CI report:

• 4a37766 Azure: FAILURE

Bot commands

The @flinkbot bot supports the following commands:

• @flinkbot run azure re-run the last Azure build

[snuyanzin]

what is the reason of this change?
We should not touch this file

we should only put here backports from Calcite and nothing more

[snuyanzin]

Please do not change Parser.jj.

If you need to change anything in this file then

1. Submit a fix to Calcite
2. once it is merged, backport to Parser.jj