fix(registry): restrict same-module suffix resolution to self/namespace receivers

[sahil-mangla]

What does this PR do?

This PR fixes #876 false-positive recursion flags (unguarded_recursion, self_recursive, recursive) occurring on store wrappers, singleton delegations, and other method calls targeting unrelated objects that happen to share a name with a top-level function in the current module (e.g. _get_store().get(...) inside get(...) or _default.check(...) inside check(...)).

Root Cause

During call graph resolution in Strategy 2 (resolve_same_module in src/pipeline/registry.c), dotted/colon-separated callee names (like _default.check) were split into prefix (_default) and suffix (check). The resolver fell back to checking if the suffix exists as a top-level function in the caller's module (module_qn.check). If a local check function was defined, it matched and mistakenly resolved the call to it, generating a self-loop CALLS edge which flagged the function as recursive.

Solution

• Introduced is_same_module_receiver to validate the receiver prefix. Suffix fallback checks in resolve_same_module are now restricted to:
  • Valid self-receivers: "self", "this", "cls", "@self".
  • Prefix matching the module/namespace name itself (or ending with .<prefix>).
• Restricting this prevents unrelated receiver calls (like axios.get, _get_store().get, _default.check) from matching same-module top-level functions, eliminating spurious CALLS self-loops.
• Added a regression test suite in tests/test_registry.c (resolve_same_module_only_on_self_receiver) to cover delegation, self, and namespace/module receiver pattern cases.

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Checklist

• Every commit is signed off (git commit -s) — required, CI rejects unsigned commits (DCO, see CONTRIBUTING.md)
• Tests pass locally (make -f Makefile.cbm test)
• Lint passes (make -f Makefile.cbm lint-ci)
• New behavior is covered by a test (reproduce-first for bug fixes)