contexthub: Add VTS target tests

Introduce target-side VTS tests covering the Context Hub HAL.

Bug: 32021659
Test: make vts -j42 && \
      vts-tradefed run commandAndExit vts --primary-abi-only \
        --skip-all-system-status-check \
	--module ContexthubHidlTargetTest
Change-Id: I387ad0cccbfa824d292e2364f175dcec21134be1