[EPIC] Refactor interface `EntityStore` to make it more elegant

[yuqi1129]

Describe the proposal

Currently, the interface EntityStore can't handle data assembled as a relation and only supports object-like entities. Temporary resolutions like SupportsTagOperations or SupportsRelationOperations are not so elegant, we'd better come up with a more suitable interface definition.

Task list

• Propose a new EntityStore interface definition. #4860
• Base Propose a new EntityStore interface definition. #4860 to replace to current EntityStore implementation.