tcc BusinessActionContext get null

Try to write a springboot dubbo tcc demo base on the dubbo-tcc-sample.
When I run my code, the parameter 'BusinessActionContext actionContext' of method 'prepare' shows null. Have tried everything I can, but still can not solve this problem.

Compare the reported Spring Boot implementation with the repository's dubbo-tcc-sample, focusing on the prepare method and its BusinessActionContext parameter. Reproduce the null value first, then trace the sample's invocation path to identify what differs and verify that the context is available when prepare runs.

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