[FLINK-39392][table] Support conditional traits for PTFs

[gustavodemorais]

What is the purpose of the change

We'd like to make PTF traits configurable so we can have multiple versions depending on how they are configured by the user.

The first suggestion: introduce a declarative addTraitWhen API on StaticArgument that allows table argument traits to vary based on the SQL call context (e.g., whether PARTITION BY is provided or scalar argument values). This replaces the static  

• As the first use case, TO_CHANGELOG now supports optional PARTITION BY:                    
• With PARTITION BY: set semantics (co-located parallel execution)  

Brief change log

• Add conditional traits with TraitContext
• Evaluate them where necessary
• Use if for the first use case TO_CHANGELOG with or without partition by
• Adjust docs and comments

Verifying this change

• Add semantic test

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? (docs / JavaDocs)

[flinkbot]

CI report:

• 4acdc14 Azure: SUCCESS

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