Pr Radar Todo

Add an item to the project TODO list at docs/proposed/TODO.md.

Workflow

1. Read the user's input ($ARGUMENTS) to determine the TODO item title and any details
2. Ask the user which t-shirt size (Small, Medium, Large) applies if not already specified
3. Read the current docs/proposed/TODO.md file
4. Append the new item under the correct size section (## Small, ## Medium, or ## Large)
5. Each item uses checkbox format: - [ ] Item title
6. If the user provided a detailed description, add it as indented text beneath the item (indented with 2 spaces)
7. Write the updated file

Item Format

- [ ] Short item title
  Longer description with more context about the idea, rationale,
  or implementation notes. Can be a full paragraph.

File Structure