refactor: use consistent file listing method (filepath.Walk vs ListMarkdownFiles)

[LudoLoops]

Issue

Two different methods are used to list markdown files:

filepath.Walk (used in most places):

• task/task.go:83 - GetTasks
• task/task.go:117 - MarkTaskDone
• task/task.go:318 - IncrementPomodoroCountForActiveTask

utils.ListMarkdownFiles (used in):

• task/finish.go:82 - FinishTask

Problem

• Inconsistent approach
• ListMarkdownFiles is less efficient (allocates full array)
• Hard to maintain two patterns

Solution

Standardize on filepath.Walk across entire codebase OR make ListMarkdownFiles a utility wrapper.

Consider:

// In utils/storage.go
func WalkMarkdownFiles(root string, fn func(path string, info os.FileInfo) error) error {
    return filepath.Walk(root, func(path string, info os.FileInfo, err error) error {
        if err != nil || info.IsDir() || !strings.HasSuffix(info.Name(), ".md") {
            return nil
        }
        return fn(path, info)
    })
}

Benefits

• Single pattern for file iteration
• More efficient than array allocation
• Easier to optimize in one place

Impact

🟢 Low - Code consistency