refactor(recipe): make search pattern configurable in file discovery

- Add SearchPattern field to Recipe struct
- Update discoverFiles to use configurable search pattern, defaulting to "if err != nil"
- Set default search_pattern in result-refactor.md recipe

.grokkit/recipes/result-refactor.md

@@ -20,6 +20,8 @@ extensions:
   go:
     - .go
 
+search_pattern: "if err != nil"
+
 allowed_shell_commands:
   - go test ./...
   - go fmt ./...

internal/recipe/runner.go

@@ -81,7 +81,7 @@ Execute this step now. Respond ONLY with the expected output format — no expla
 	return nil
 }
 
-// discoverFiles — fully generic using recipe metadata + smart defaults
+// discoverFiles — fully generic using recipe metadata
 func (r *Runner) discoverFiles() []string {
 	var files []string
 
@@ -110,14 +110,19 @@ func (r *Runner) discoverFiles() []string {
 		}
 	}
 
+	// 4. Use the configurable search pattern (defaults to "if err != nil")
+	searchFor := r.Recipe.SearchPattern
+	if searchFor == "" {
+		searchFor = "if err != nil"
+	}
+
 	_ = filepath.WalkDir(root, func(path string, d os.DirEntry, err error) error {
 		if err != nil || d.IsDir() {
 			return nil
 		}
 		if allowedExt[filepath.Ext(path)] {
-			// For now we still look for "if err != nil" — we can generalize this later with a recipe hint if needed
 			b, _ := os.ReadFile(path)
-			if strings.Contains(string(b), "if err != nil") {
+			if strings.Contains(string(b), searchFor) {
 				files = append(files, path)
 			}
 		}

internal/recipe/types.go

@@ -10,6 +10,7 @@ type Recipe struct {
 	// Generic discovery support (option 2)
 	ProjectLanguages []string            `yaml:"project_languages"`
 	Extensions       map[string][]string `yaml:"extensions"`
+	SearchPattern    string              `yaml:"search_pattern"` // new
 
 	// Resolved runtime values from --param flags
 	ResolvedParams map[string]any `yaml:"-"`