[Feat] A group of new minor features for v0.2.0

[noisrucer]

Description

1. Multi-select tasks for done command (ex. done 1 15 18 20)
2. Add complete status instead of only being able to delete a task (colored icons for status)
3. Meta-data of a task.
   • Markdown editor
   • View the markdown file in a nicely-formatted TUI box
4. flush command to delete a group of tasks easily
   • flush --past: delete all passed tasks
   • flush --complete: delete all completed tasks (from 2)
5. Support powerful task statistics
   • How many tasks are completed/remaining for today, each category, total, etc.
6. User-customized key bindings
7. Add more colors for category (probably up to 10~13)
8. A way to deal with a small-width monitor (category tree is cut off)
9. Recurring events
   • Recurring on one or multiple weekdays
   • Recurring everyday
10. Weekly schedule command (Current week)
    • Also support TUI like calendar?
    • Or just print it out in the terminal?
11. Password recovery
12. Support --color option for creating a category

Purpose

Comments

The above features will be added altogether at once to avoid frequent minor updates.