Restore full indexing test coverage (239 tests)

The parameterization accidentally removed most test cases, reducing
from 239 @test statements to only 38. Restored the original test file
which provides comprehensive coverage of all indexing operations.

Note: Indexing tests use scalar indexing (v.v[i], A.A[i,j]) which is
inherently CPU-only, so GPU parameterization is not applicable.

Author: Sébastien Loisel