prefer Glob over Files in Patterns() instead of merging both

When both glob: and files: are set on the same override or
kind-assignment entry, Patterns() previously returned the
union of both, silently broadening the match set. Now Glob
takes precedence and Files is used only when Glob is absent,
which matches the documented deprecation semantics.

https://claude.ai/code/session_01NEgDS5N2TCk6KyYfKxrJP8

Author: claude

internal/config/config.go

@@ -92,10 +92,14 @@ type Override struct {
 	Categories map[string]bool    `yaml:"categories"`
 }
 
-// Patterns returns the effective set of glob patterns for the override,
-// combining the canonical Glob field with the deprecated Files alias.
+// Patterns returns the effective set of glob patterns for the override.
+// When Glob is set it takes precedence; Files is used only when Glob is
+// absent (backward compatibility with the deprecated files: key).
 func (o Override) Patterns() []string {
-	return append(o.Glob, o.Files...)
+	if len(o.Glob) > 0 {
+		return o.Glob
+	}
+	return o.Files
 }
 
 // KindBody is a named bundle of rule settings. It has the same shape as
@@ -117,10 +121,14 @@ type KindAssignmentEntry struct {
 	Kinds []string `yaml:"kinds"`
 }
 
-// Patterns returns the effective set of glob patterns for the entry,
-// combining the canonical Glob field with the deprecated Files alias.
+// Patterns returns the effective set of glob patterns for the entry.
+// When Glob is set it takes precedence; Files is used only when Glob is
+// absent (backward compatibility with the deprecated files: key).
 func (e KindAssignmentEntry) Patterns() []string {
-	return append(e.Glob, e.Files...)
+	if len(e.Glob) > 0 {
+		return e.Glob
+	}
+	return e.Files
 }
 
 // RuleCfg is a YAML union: can be bool (enable/disable) or map[string]any (settings).