test(oss-licenses): add Issue 397 regression test and build logging

[timothyfroehlich]

This PR adds a regression test for Issue 397 (double-tap crash in V2 activity) and introduces version logging in the testapp's app module.

Additionally, this PR refactors the E2E test infrastructure for better reliability and performance:

• Replaced the manual deny-list for testapp inputs with a robust prepareTestApp Sync task using an allow-list.
• Fixed E2E test cache invalidation by properly tracking testapp source changes as task inputs.
• Simplified EndToEndTest.kt by removing redundant file filtering and using a clean, pre-processed project directory.
• Excluded Gradle wrapper files from testapp copying, as GradleRunner handles version selection dynamically.

The regression test verifies that rapid double-tapping on the Up button no longer causes an IllegalArgumentException.

All tests are confirmed passing against the publicly released 17.5.1 library version.