Allow writing a comment to capture new insights gained after completing a lifewheel reflection - and what to focus on for the next week

[Greenheart]

• From a UX perspective, this feature could add much more depth and value to each reflection. It would also make it more fun to look back on historical reflections, and understand what happened at that point in life. Why did you feel a certain way? What do you want to focus on in the coming week?

Implementation

• Implementing this would require a new protocol version, since the data format changes.
• We would also need to update the encoding to handle variable length data. Either write a custom implementation, or look into other solutions for this. Should be doable, since we know the length of each variable length field, and could encode that as an int32 (2 M characters) or int16 (32 k characters), depending on what should be the max length of the text entered by the user.

implementation ideas

• maybe use https://github.com/dmonad/lib0 and the module lib0/encoding for variabler lengrh encoding.