feat: curve A/P PIP for collections (rebase of #1322)

[grootstebozewolf]

Summary

Rebase of @dbaston’s #1322 onto current main (that PR is CONFLICTING). Same feature, merge conflicts resolved, plus a small empty-point-set hardening.

Behaviour (from #1322)

• SimplePointInAreaLocator::isAnyPointContained / isEveryPointContained for multi-point vs multi-surface
• Curved A/P paths for contains / intersects / disjoint (incl. MultiSurface)
• Tests: MultiPoint×MultiSurface, PostGIS #5832 intersects pin
• Keeps existing automatic-linearization CAPI tests (merged alongside)

Extra on this rebase

• Empty point sets: isAny → false, isEvery → true (vacuous); null-safe getCoordinate
• CAPI tests for empty MULTIPOINT / POINT EMPTY on contains / intersects / disjoint

Supersedes / unblocks #1322. Happy for @dbaston to take over authorship if preferred.

Test plan

• Conflict markers resolved; branch builds on GitHub CI
• CI green on this PR
• Manual: MultiSurface contains interior MultiPoint; exterior point fails contains; empty MultiPoint vacuous contains / disjoint

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Co-authored-by: Dan Baston (original #1322)
Assisted-by: xAI Grok (rebase + empty multipoint guards)

[grootstebozewolf]

Next rung — local verification + Contains semantics fix

CI status: workflows show action_required (first-time contributor; needs a maintainer to approve the run).

Local self-check (WSL, Release, test_geos_unit):

Suite	Result
capi::GEOSContains	14/14
capi::GEOSIntersects	17/17
capi::GEOSDisjoint	5/5

Extra commit on this PR: DE-9IM Contains for curved A/P was using “in or on” (!= EXTERIOR), i.e. covers-like. Fixed via isAreaContainingPoints:

• empty point set → false (needs II=T)
• boundary-only → false
• boundary + interior multipoint → true
• boundary still intersects

@dbaston (or any maintainer): please approve CI when you have a moment.

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Assisted-by: xAI Grok

[grootstebozewolf]

Rebased onto post-#1500 main

#1500 (GeometrySplitter / GeometryNoder for #1497) is merged — rebased this branch cleanly onto current main (14fd2d7).

Force-pushed feat/curve-pip-collections-rebase (same 4 commits, new hashes). Still mergeable; still needs maintainer CI approval (first-time contributor).

Local (WSL Release) after rebase: capi::GEOSContains 14/14, GEOSIntersects 17/17, GEOSDisjoint 5/5; MultiSurface×MultiPoint A/P pins green via geosop.

Next GEOS rung (oracle-driven): #1505 for covers L/P float robustness (#968).

Assisted-by: xAI Grok

[dbaston]

Please try to limit the verbosity of these pull requests.

I'm going to close this -- I don't think these special-case implementations are worth it when a curve-aware predicate engine should be in the future.