The current logic for SQL dialect conversion is all in the `fe-core` module, which may lead to the following issues:
- Changes to the dialect conversion logic may occur frequently, requiring users to upgrade the Doris version frequently within the fe-core module, leading to a longer change cycle.
- The cost of customized development is high, requiring users to replace the fe-core JAR package.
Turning it into a plugin can address the above issues properly.
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