fix: mixin/protocol schema suffix

[project0]

fix feature and wrong behavior introduced by #146

• fix CompareDir early-returning after first subdirectory, causing remaining files to be skipped in integration test comparison

• fix Mixin/Protocol schema suffix protection applying to property field names instead of generated schema type names: remove suffix logic from kclName (which is shared between property and schema naming) and add a protectedSchemaName helper applied only at inline schema creation in buildProperties

• add integration test case suffix_protected_mixin_protocol covering CRD properties whose names end with Mixin or Protocol

1. Does this PR affect any open issues?(Y/N) and add issue references (e.g. "fix #123", "re #123".):

• N
• Y

2. What is the scope of this PR (e.g. component or file name):

3. Provide a description of the PR(e.g. more details, effects, motivations or doc link):

• Affects user behaviors
• Contains syntax changes
• Contains variable changes
• Contains experimental features
• Performance regression: Consumes more CPU
• Performance regression: Consumes more Memory
• Other

4. Are there any breaking changes?(Y/N) and describe the breaking changes(e.g. more details, motivations or doc link):

• N
• Y

5. Are there test cases for these changes?(Y/N) select and add more details, references or doc links:

• Unit test
• Integration test
• Benchmark (add benchmark stats below)
• Manual test (add detailed scripts or steps below)
• Other

[project0]

tests are failing because of some race conditions with not using proper atomic tmp files/folders. I tried fixing those, but it is a bigger task that justifies a extra PR. Nevertheless, the flaky tests are unrelated to the PR.