[FLINK-38262][table] add CreateConnectionOperation and converter

[Shekharrajak]

What is the purpose of the change

Adds CreateConnectionOperation and SqlCreateConnectionConverter to translate SqlCreateConnection AST nodes into executable Operations.

Brief change log

Adds CreateConnectionOperation and SqlCreateConnectionConverter

Verifying this change

unit tests

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: (yes / no / don't know)
• The S3 file system connector: (yes / no / don't know)

Documentation

• Does this pull request introduce a new feature? (yes / no)
• If yes, how is the feature documented? (not applicable / docs / JavaDocs / not documented)

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

Yes

[flinkbot]

CI report:

• 3f78fab Azure: FAILURE

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[Shekharrajak]

@lihaosky @snuyanzin Please have a look - If these structure looks good, we can have other Operation & converter implemented for the respective SQL AST node.

Followup PRs will have:

DropConnectionOperation, SqlDropConnectionConverter
DropConnectionOperation, SqlDropConnectionConverter
AlterConnectionRenameOperation, SqlAlterConnectionRenameConverter
ShowConnectionsOperation, SqlShowConnectionsConverter
ShowCreateConnectionOperation, SqlShowCreateConnectionConverter
DescribeConnectionOperation, SqlRichDescribeConnectionConverter

[lihaosky]

Thanks @Shekharrajak for the contribution. I left some comments.

[Shekharrajak]

Please have a look on new changes according to your review @lihaosky