[Improve][Zeta] Introduce MapStorage interface to decouple from Hazelcast IMap

[dybyte]

Purpose of this pull request

This PR extracts the storage layer so that the engine is no longer tightly coupled to Hazelcast IMap. This decoupling makes it easier to introduce alternative storage implementations in the future.(e.g. RocksDB)

Does this PR introduce any user-facing change?

No.

How was this patch tested?

Covered by existing tests.

Check list

• [ ] If any new Jar binary package adding in your PR, please add License Notice according New License Guide
• [ ] If necessary, please update the documentation to describe the new feature. https://github.com/apache/seatunnel/tree/dev/docs
• [ ] If necessary, please update incompatible-changes.md to describe the incompatibility caused by this PR.
• [ ] If you are contributing the connector code, please check that the following files are updated:
  1. Update plugin-mapping.properties and add new connector information in it
  2. Update the pom file of seatunnel-dist
  3. Add ci label in label-scope-conf
  4. Add e2e testcase in seatunnel-e2e
  5. Update connector plugin_config

[chl-wxp]

good job

[dybyte]

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