Add recursive directory search with depth limits

internal/engine/glob.go

@@ -10,6 +10,8 @@ import (
 
 const globReadBatch = 128
 
+var errInvalidImportGlobPattern = errors.New("invalid import glob filename pattern")
+
 type globCandidate struct {
 	absolute string
 	relative string
@@ -99,27 +101,21 @@ func (s *importTraversal) readGlobMatches(directory, pattern string, location Lo
 		return nil, []Diagnostic{importDiagnostic(CodeImportOutsideRoot, "glob directory could not be addressed inside the configuration root", &location)}
 	}
 	var matches []string
-	var problem *Diagnostic
-	err = s.access.readDirectory(canonical, func(entry fs.DirEntry) bool {
-		s.accounting.entries++
-		if s.accounting.entries > s.limits.entries {
-			value := importDiagnostic(CodeImportLimitExceeded, "glob traversal exceeds the directory-entry visit limit", &location)
-			problem = &value
-			return false
-		}
+	err = visitBoundedImportDirectory(s.access, canonical, s.limits.entries, s.accounting, func(entry fs.DirEntry) error {
 		matched, matchErr := path.Match(pattern, entry.Name())
 		if matchErr != nil {
-			value := importDiagnostic(CodeImportInvalid, "import glob pattern is invalid", &location)
-			problem = &value
-			return false
+			return errInvalidImportGlobPattern
 		}
 		if matched {
 			matches = append(matches, entry.Name())
 		}
-		return true
+		return nil
 	})
-	if problem != nil {
-		return nil, []Diagnostic{*problem}
+	if errors.Is(err, errImportDirectoryEntryLimit) {
+		return nil, []Diagnostic{importDiagnostic(CodeImportLimitExceeded, "glob traversal exceeds the directory-entry visit limit", &location)}
+	}
+	if errors.Is(err, errInvalidImportGlobPattern) {
+		return nil, []Diagnostic{importDiagnostic(CodeImportInvalid, "import glob pattern is invalid", &location)}
 	}
 	if errors.Is(err, fs.ErrNotExist) {
 		return nil, nil