too many type systems in source code but serves same purpose

- https://github.com/4paradigm/OpenMLDB/blob/ff7e8acf21ead1f9734eef59ac3521adb05dff2e/hybridse/include/node/node_enum.h#L154-L165
- https://github.com/4paradigm/OpenMLDB/blob/ff7e8acf21ead1f9734eef59ac3521adb05dff2e/hybridse/src/proto/fe_type.proto#L21-L27
- https://github.com/4paradigm/OpenMLDB/blob/ff7e8acf21ead1f9734eef59ac3521adb05dff2e/src/proto/type.proto#L25-L32
- `base::StringRef, base::Timestamp` .. etc in udf system
- https://github.com/4paradigm/OpenMLDB/blob/ff7e8acf21ead1f9734eef59ac3521adb05dff2e/hybridse/include/sdk/base_schema.h#L27-L32

And also different implementations build upon those type systems,

The issue points to multiple type definitions across hybridse/include/node/node_enum.h, hybridse/src/proto/fe_type.proto, src/proto/type.proto, and base_schema.h. Start by examining each linked file to understand the overlapping type systems. Look for how these types are used in the UDF system and other implementations. Determine a strategy to unify or reduce duplication, which requires deep knowledge of the codebase's architecture.

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