[FLINK-33392][docs] Add the documentation pages for balanced tasks scheduling.

[RocMarshal]

What is the purpose of the change

[FLINK-33392][docs] Add the documentation pages for balanced tasks scheduling.

Brief change log

[FLINK-33392][docs] Add the documentation pages for balanced tasks scheduling.

Verifying this change

N.A

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

• Dependencies (does it add or upgrade a dependency): (yes / no)
• The public API, i.e., is any changed class annotated with @Public(Evolving): (yes / no)
• The serializers: (yes / no / don't know)
• The runtime per-record code paths (performance sensitive): (yes / no / don't know)
• 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)

[flinkbot]

CI report:

• 811f8e4 Azure: FAILURE

Bot commands

The @flinkbot bot supports the following commands:

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

[RocMarshal]

The CH edition page will added a copy in the corresponding location after the EN edition page is ready.

[davidradl]

I was expecting this file to be duplicated in the Chinese docs tree.

[RocMarshal]

Yes, as described in #27128 (comment) , The page will be added after the english edition is ready to merge.

[davidradl]

ok - but this is unusual. Normally we would do both together.

[RocMarshal]

Thanks @davidradl .

I'll follow the rule you mentioned in next related contributions.

And I added the related page.

[davidradl]

I was expecting is as close as possible be as as close as possible to ...

[RocMarshal]

nice idea! Updated.

Please help take a look , @davidradl thanks a lot !