fix: exclude annotation types from mapper candidate components

[seonwooj0810]

Fixes #1032

Problem

ClassPathMapperScanner#isCandidateComponent accepted any independent interface:

return beanDefinition.getMetadata().isInterface() && beanDefinition.getMetadata().isIndependent();

Annotation types (@interface) are interfaces at the bytecode level and report isInterface() == true / isIndependent() == true. So an annotation declared inside a scanned base package passed this check and was wrongly registered as a MapperFactoryBean, as noted in #1032.

Fix

Also require !metadata.isAnnotation(), so annotation types are excluded while regular mapper interfaces in the same package continue to be scanned.

Test evidence

Added ClassPathMapperScannerAnnotationTest, which scans a package containing both a regular mapper interface and an annotation type, and asserts the mapper interface is registered while the annotation type is not. The test fails on master (the annotation type bean definition scanMarkerAnnotation is present) and passes with this change.

The supporting types live in a dedicated, otherwise-unscanned package (org.mybatis.spring.scancandidate) so existing scanner tests are unaffected.

./mvnw test -Dlicense.skip=true — Tests run: 223, Failures: 0, Errors: 0, Skipped: 15 (BUILD SUCCESS).

Verification done: (1) no in-flight PR for the issue; (2) no claim comments on the thread; (3) code-focused change in ClassPathMapperScanner.java; (4) confirmed the pattern still exists on current master; (5) reproduced the bug with a failing test before applying the fix.