fix(zig): address gitnexus-check findings on 215f70e3

- receiver-bound Case 3 wraps its reason in constructionSiteReason, like
  Case 1 and the nested-type route of Case 2 (one vocabulary per provider)
- resolveZigImportInternal rejects drive-qualified absolute imports
  (C:\foo.zig), the same test normalizeZigDepPath applies; unit case added
- the compound resolver's chain seed also tries the whole receiver as the
  qualified class (opmod.Op), as a bare class-name head already does
- markConstructionSites contract text names the receiver-bound routes

The return_type field claim is refuted: tree-sitter-zig exposes a fn's
return type as the type field (checked on the grammar).

gitnexus/src/core/ingestion/import-resolvers/zig.ts

@@ -113,7 +113,11 @@ export function resolveZigImportInternal(
   // `@import("/abs.zig")` as an import outside the module path). Splitting
   // would drop the empty leading component and read `/foo.zig` as an
   // importer-relative `foo.zig`, fabricating an in-repo edge.
-  if (trimmed.startsWith('/')) return null;
+  // A drive-qualified spelling (`C:/foo.zig`, normalized from `C:\foo.zig`)
+  // is absolute too: it carries a `/`, so without this guard it would take
+  // the importer-relative branch and probe `src/C:/foo.zig`. Same test as
+  // `normalizeZigDepPath`.
+  if (trimmed.startsWith('/') || /^[A-Za-z]:\//.test(trimmed)) return null;
 
   // Path-bearing import: resolve relative to the current file's directory.
   // Zig allows both "./foo.zig" and "foo.zig" — both are filesystem-relative.

gitnexus/src/core/ingestion/scope-resolution/contract/scope-resolver.ts

@@ -897,8 +897,11 @@ export interface ScopeResolver {
    * The marker rides in `reason` because relationships carry no arbitrary
    * properties (adding one moves SCHEMA_FINGERPRINT — the IMPLEMENTS
    * `-pointer` precedent in `pipeline/run.ts`). Applies to the free-call
-   * fallback and the reference bridge; receiver-qualified construction sites
-   * are not tagged `constructor` by any provider today.
+   * fallback, the reference bridge and the receiver-bound paths — a
+   * namespace-qualified literal (`mod.T{…}`, Case 1), a type nested in the
+   * receiver's class (`A.Item{}`, Case 2) and a dotted type binding (Case 3)
+   * all go through `constructionSiteReason` — so an opted-in provider sees
+   * one vocabulary whichever path resolved the site.
    */
   readonly markConstructionSites?: boolean;
 

gitnexus/src/core/ingestion/scope-resolution/passes/compound-receiver.ts

@@ -1204,10 +1204,12 @@ export function resolveCompoundReceiverClass(
   // itself, so a variant / static member hop is read off the class scope),
   // and the remaining segments are walked as members. Longest first: the
   // prefix is a class, not a value, and `a.B.C` must seed at `C`, not stop
-  // at `B` and read `C` as a member of it.
+  // at `B` and read `C` as a member of it. The whole receiver may be the
+  // class (`opmod.Op` — no member segment left), exactly as a bare class
+  // name head resolves to the class constant above.
   let firstHop = 1;
   if (currentClass === undefined && headType === undefined && options.resolveQualifiedClass) {
-    for (let k = parts.length - 1; k >= 2; k--) {
+    for (let k = parts.length; k >= 2; k--) {
       const prefix = parts.slice(0, k).join('.');
       if (prefix.includes('(')) continue;
       const seeded = options.resolveQualifiedClass(prefix, inScope);

gitnexus/src/core/ingestion/scope-resolution/passes/receiver-bound-calls.ts

@@ -1771,7 +1771,15 @@ export function emitReceiverBoundCalls(
                   nodeLookup,
                   site,
                   memberDef,
-                  memberDef.filePath !== parsed.filePath ? 'import-resolved' : 'global',
+                  // Same marker rule as Case 1 / Case 2: a constructor-form site
+                  // reached through a dotted type binding keeps its
+                  // ` (constructor)` suffix when the provider opted in; for
+                  // every other provider the string is unchanged.
+                  constructionSiteReason(
+                    memberDef.filePath !== parsed.filePath ? 'import-resolved' : 'global',
+                    site,
+                    provider.markConstructionSites,
+                  ),
                   seen,
                   // Explicit defaults so the trailing capture ctx (#2227 U2) can
                   // be threaded without changing dedup/confidence behavior.

gitnexus/test/unit/zig-import-resolver.test.ts

@@ -64,6 +64,11 @@ describe('resolveZigImportInternal', () => {
     expect(resolveZigImportInternal('src/main.zig', '/src/foo.zig', files)).toBeNull();
     // Backslash-spelled absolute paths normalize to the same rejection.
     expect(resolveZigImportInternal('src/main.zig', '\\foo.zig', files)).toBeNull();
+    // A drive-qualified spelling carries a `/` after normalization and used to
+    // take the importer-relative branch (probing `src/C:/foo.zig`).
+    const drive = new Set<string>([...files, 'src/C:/foo.zig']);
+    expect(resolveZigImportInternal('src/main.zig', 'C:\\foo.zig', drive)).toBeNull();
+    expect(resolveZigImportInternal('src/main.zig', 'C:/foo.zig', drive)).toBeNull();
     // The relative spelling next to it still resolves.
     expect(resolveZigImportInternal('src/main.zig', 'foo.zig', files)).toBe('src/foo.zig');
   });