feat(bindings): tnumber distance — <->, nad, nearestApproachDistance

[estebanzimanyi]

Summary

Adds 10 ScalarFunction registrations for tnumber distance:

SQL	MEOS	Returns
tint <-> tint	tdistance_tnumber_tnumber	tint
tfloat <-> tfloat	tdistance_tnumber_tnumber	tfloat
nad(tint, INTEGER)	nad_tint_int	INTEGER
nad(tint, tint)	nad_tint_tint	INTEGER
nad(tfloat, DOUBLE)	nad_tfloat_float	DOUBLE
nad(tfloat, tfloat)	nad_tfloat_tfloat	DOUBLE
nearestApproachDistance(...)	(4 aliases for the nad set)	(matching)

Implementation uses templated helpers from PR #27 plus per-call BinaryExecutor blocks for the scalar-returning nad variants.

Intentionally NOT registered (documented MEOS-side issue)

Value-distance variants <-> for (tint, INTEGER) / (INTEGER, tint) / (tfloat, DOUBLE) / (DOUBLE, tfloat). In the installed MEOS library, tdistance_tfloat_float / tdistance_tint_int return the temporal's own value at each instant rather than the |t.value - v| absolute difference. Smoke verified:

SELECT 5.0::DOUBLE <-> tfloat '5.0@2000-01-01';   -- returns 5.0, expected 0.0
SELECT 100.0::DOUBLE <-> tfloat '2.5@2000-01-01'; -- returns 2.5, expected 97.5

The wrapper implementations stay in the header and .cpp so the registrations can be uncommented in src/temporal/temporal.cpp once the MEOS upstream is fixed.

Smoke test (working surface)

SELECT tfloat '[1@01-01, 5@01-05]' <-> tfloat '[3@01-01, 3@01-05]';
-- [2@01-01, 0@01-03, 2@01-05]   (linear-interpolated, touches 0 at midpoint)

SELECT nad(tint '[1@01-01, 5@01-05]', 3);
-- 0

SELECT nad(tfloat '[1@01-01, 5@01-05]', tfloat '[3@01-01, 3@01-05]');
-- 0.0

Test plan

• make release then TZ=UTC ./build/release/test/unittest "<proj>/test/*" — full suite passes.
• After merge, PR test(parity): batch 2 — boolops / textfuncs / compops / posops / aggfuncs #24's 036_tnumber_distance.test skip block partially unwraps (the temporal-temporal and nad/nearestApproachDistance queries become active; the value-temporal <-> queries stay skipped pending MEOS fix).

Dependencies

Stacked on PR #30 (tnumber unary). Merge order: #27 → #29 → #30 → this.

[estebanzimanyi]

Consolidated into #43 (tnumber numeric functions — arithmetic + unary + distance).