Fix/comp terminal predicate rtl

[guosran]

Summary

Addresses #292 with a minimized terminal compare predicate fix. This PR only updates CompRTL.py and its focused test.

Changes

• Let terminal EQ_CONST/NE_CONST comparisons produce the loop-control predicate when the vector factor is reached.
• Add a concrete example as an inline test comment.

No new ports or interfaces are introduced.

[guosran]

This PR is intentionally separated from #297 because the predicate semantics may need discussion. The intended case is terminal loop comparison: when the vector factor is reached, EQ_CONST/NE_CONST produces the loop-control predicate even if the incoming data token predicate is false.

[guosran]

Concrete example:
A terminal comparison should preserve predicate behavior when using const comparisons.

input payload = 7, predicate = 1
operation = >= const 7

Expected:
output indicates true and remains predicated.

If predicate is 0:
comparison result should not become an active terminal result.