fix(extract): apply interop guard to type-match stub rewire (#2343)

[HaoChiBao]

Summary

• Hoist the Cross-module references to functions land on a name-only stub node — _rewire_unique_stub_nodes excludes function labels #1781 language-family interop gate in _rewire_unique_stub_nodes so it applies to unique type matches (exact + case-insensitive), not only the function fallback.
• Stops Swift/Python Path stubs from binding to a lone JS class Path, which was inventing phantom cross-language edges and inflating betweenness/god-nodes.
• Fixes Interop guard missing on the type-match branch of stub resolution: Swift/Python Path binds to a JS class #2343. Legitimate same-family and native-family (Swift↔ObjC) rewires are unchanged.

Test plan

• Unit: cross-language type stub blocked; same-family type rewire; native Swift→ObjC still resolves
• Existing Cross-module references to functions land on a name-only stub node — _rewire_unique_stub_nodes excludes function labels #1781 function rewire tests still pass
• Updated inheritance fixture to same-family C#→C# (old C#→Python relied on the bug)
• Issue repro (three.js + Shape.swift + build.py): 0 cross-lang edges to JS Path; three distinct Path nodes
• pytest tests/test_cross_language_call_resolution.py + rewire/inheritance extract tests

[graphify-labs]

Looks safe to merge — no coupling regressions and no blocking issues, checked against the code graph (not a self-assessment).

Graphify reviewed this change.

Looks safe to merge — no coupling regressions and no blocking issues, checked against the code graph (not a self-assessment).

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Graphify review — findings

This PR modifies the _rewire_unique_stub_nodes function in graphify/extract.py to apply the existing language-family interop gate to all unique-stub rewire matches (type exact, type case-insensitive, and function fallback), rather than only to the function fallback path. The intent, per referenced issue #2343, is to prevent a stub type reference in one language from binding to a same-named definition in an unrelated language family. The test file is updated to change an existing fixture from a cross-language (Python→C#) pair to a same-language (C#) pair, and adds three new tests covering cross-language type rewire blocking, same-family type rewiring, and native-family (Swift/ObjC) interop rewiring.

No blocking issues surfaced. 3 lower-confidence candidates did not survive cross-model review.

Analysis details — impact, health, verification

Impact & health

Graphify review

Impact — 1366 functions depend on the 467 functions this change touches.

Health — this change adds coupling hotspots:

• worse: _rewire_unique_stub_nodes() — 9 callers, 6 callees

Verification — 1366 functions in the blast radius were not formally verified this run (proofs are advisory here).

Gate & verification

graphify gate

PASS — objectively clean (no health regressions, tests not run — proofs not run this pass (advisory)). Grounded, not self-assessed.

Advisory (not blocking):

• verification_scope: 1239 function(s) in the blast radius were not formally verified this run

· 1 more finding(s) on lines outside this diff (see the check run).