fix: correct scale rule count query(#6870)

[juicewcode]

Fixes #6870
Fix the invalid and inconsistent scale_rule count query

Changes

• Wrap countByQuery conditions with MyBatis <where>.
• Change metric filtering from exact match to LIKE CONCAT('%', ..., '%').
• Add mapper integration tests for filtered and unfiltered count queries.

Make sure that:

• You have read the contribution guidelines.
• You submit test cases (unit or integration tests) that back your changes.
• Your local test passed ./mvnw clean install -Dmaven.javadoc.skip=true.