Range IsInfinity/IsFinite translations are never executed against PostgreSQL; a wrong composition passes every suite #118

The single-range state predicates IsInfinity() and IsFinite() translate to compositions of lower_inf, upper_inf and isempty (ValueRangesMethodCallTranslator.cs, the IsInfinityMethod / IsFiniteMethod arms), and nothing executes them against PostgreSQL. The only guard is QueryTranslationTests.Range_IsInfinity_ComposesBothUnboundedChecks, which asserts substrings: lower_inf(b."Period"), upper_inf(b."Period") and "AND".

Seeded on a scratch clone of main (7f4dc47): IsInfinity → lower_inf(x) AND NOT upper_inf(x). Every suite stayed green —

— while the seeded SQL answers true for (,5] and false for (,), the opposite of memory. The multirange forms are covered (MultirangeShapePredicates_MatchInMemory executes them per shape); the range forms are not.

Test to add: execute IsEmpty, IsInfinity, IsFinite, IsUnboundedStart and IsUnboundedEnd on a range column for all five shapes and compare each with the in-memory answer, as the multirange test does. Keep the seed as test/oracles/seeds/range-isinfinity-composition.patch naming that test. The QueryTranslationTests substring assertions can then assert the whole expression rather than fragments.

Found in the 10.0.0 bug hunt (code-analyst seeding, reproduced here). Tests only; the shipped translation is right.