fix(r): limit library() wildcard expansion to top-level definitions

expandRWildcardNames walked the flat localDefs of the target file and filtered
only dotted names, so a function nested inside another function
(`outer <- function() { helper <- function() 1 }`) was offered as a
package-level name to every file that calls library()/require() on the package.

Reproduction: two new cases in r-dotted-s3-hooks.test.ts failed on the
unfixed code (['outer', 'helper', 'top'] instead of ['outer', 'top'];
['a', 'b', 'c', 'd'] instead of ['a']). The expansion now keeps only names bound
at module scope (rFileTopLevel().names, which already feeds the dotted-tail
guard); top-level functions and bare-call S4/R6 classes are still listed
(controls added; test/integration/resolvers/r.test.ts unchanged and green).

gitnexus/src/core/ingestion/languages/r/scope-resolver.ts

@@ -104,7 +104,8 @@ function emitRVirtualHeritageEdges(
 }
 
 /**
- * Enumerate all top-level names exported from a target module scope's file.
+ * Enumerate all top-level names exported from a target module scope's file
+ * (module-scope function and class bindings; functions nested in another function are not).
  * `library()`/`require()` are R's wildcard imports — every top-level name of
  * the named local package becomes visible, UNFILTERED by NAMESPACE (a
  * `library()`/`require()` call brings the whole package's namespace into
@@ -127,12 +128,15 @@ export function expandRWildcardNames(
 ): readonly string[] {
   const target = parsedFiles.find((p) => p.moduleScope === targetModuleScope);
   if (target === undefined) return [];
-  const { dottedTails } = rFileTopLevel(target);
+  const { names: topLevel, dottedTails } = rFileTopLevel(target);
   const seen = new Set<string>();
   const names: string[] = [];
   for (const def of target.localDefs) {
     const qn = def.qualifiedName;
-    if (qn === undefined || qn.length === 0 || qn.includes('.')) continue; // top-level only
+    if (qn === undefined || qn.length === 0 || qn.includes('.')) continue; // no dotted names
+    // `localDefs` is flat: it also lists functions nested in other functions, which a
+    // `library()` does not bring into scope. Only module-scope bindings are top-level.
+    if (!topLevel.has(qn)) continue;
     if (dottedTails.has(qn)) continue; // shares its tail with an S3 method: see above
     if (seen.has(qn)) continue;
     seen.add(qn);

gitnexus/test/unit/scope-resolution/r/r-dotted-s3-hooks.test.ts

@@ -104,6 +104,39 @@ describe('expandRWildcardNames', () => {
     ).toEqual(['Scorer', 'tidy']);
   });
 
+  it('lists only top-level definitions, not functions nested in another function', () => {
+    expect(
+      names('outer <- function() {\n  helper <- function() 1\n  helper()\n}\ntop <- function() 2'),
+    ).toEqual(['outer', 'top']);
+  });
+
+  it('does not list a function nested several levels deep or inside a control block', () => {
+    expect(
+      names(
+        [
+          'a <- function() {',
+          '  b <- function() {',
+          '    c <- function() 1',
+          '  }',
+          '  if (TRUE) d <- function() 2',
+          '}',
+        ].join('\n'),
+      ),
+    ).toEqual(['a']);
+  });
+
+  it('still lists top-level classes alongside top-level functions', () => {
+    expect(
+      names('Scorer <- R6::R6Class("Scorer", public = list(f = function() 1))\nrun = function() 1'),
+    ).toEqual(['Scorer', 'run']);
+  });
+
+  it('still lists an S4 class defined by a bare setClass() call', () => {
+    expect(
+      names('setClass("Shape", representation(n = "numeric"))\nplain <- function() 1'),
+    ).toEqual(['Shape', 'plain']);
+  });
+
   it('never lists dotted names themselves', () => {
     expect(names('print.foo <- function(x) x')).toEqual([]);
   });