maintainer: New scheduling algorithm for basic schedule

[hongyunyan]

What problem does this PR solve?

Issue Number: close #xxx

What is changed and how it works?

This PR introduces a new dynamic load-balancing scheduling algorithm for basic scheduler for maintainer, designed to optimize incremental data synchronization performance.

New scheduling allocates the replication tasks based on incremental data scanning rate on the nodes. Besides, we limit the upper concurent replication tasks to ensure that replication tasks are dispatched in batches on demand to maximize balanced resource utilization

Check List

Tests

• Unit test
• Integration test
• Manual test (add detailed scripts or steps below)
• No code

Questions

Will it cause performance regression or break compatibility?

Do you need to update user documentation, design documentation or monitoring documentation?

Release note

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@hongyunyan: The following tests failed, say /retest to rerun all failed tests or /retest-required to rerun all mandatory failed tests:

Test name	Commit	Details	Required	Rerun command
pull-check	9f518c6	link	true	/test pull-check
pull-unit-test	9f518c6	link	true	/test pull-unit-test
pull-cdc-pulsar-integration-light	9f518c6	link	false	/test pull-cdc-pulsar-integration-light
pull-cdc-kafka-integration-light	9f518c6	link	false	/test pull-cdc-kafka-integration-light
pull-cdc-mysql-integration-heavy	9f518c6	link	true	/test pull-cdc-mysql-integration-heavy

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