Add a hint about using todos for complicated tasks

[mrubens]

Important

Adds a hint in formatReminderSection in reminder.ts to use update_todo_list for complicated tasks when the todo list is empty.

• Behavior:
  • Updates formatReminderSection in reminder.ts to return a hint about using update_todo_list for complicated tasks when the todo list is empty.

^{This description was created by for cc01357. You can customize this summary. It will automatically update as commits are pushed.}

[delve-auditor]

✅ No security or compliance issues detected. Reviewed everything up to cc01357.

Security Overview

• 🔎 Scanned files: 1 changed file(s)

Detected Code Changes

Change Type	Relevant files
Enhancement	► reminder.ts     Add hint text for empty todo list

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