Todo Description

[gitKashish]

Description for each TODO

Create description for every TODO. The description must be a proper Markdown Document.

This is part of the effort to integrate AI into pluto-todos and summarize and organize notes in the near future.

Expected Functionalities

1. Create a todo and then add a description to it once added with a single interaction.
2. Add markdown for each todo, render the markdown beautifully.
3. Code blocks, snippets and tables must work (no exception).