## Notion ticket link
<!-- Please replace with your ticket's URL -->
[Intake Forms - add Additional Information
Page](https://www.notion.so/uwblueprintexecs/Intake-Forms-add-Additional-Information-Page-28010f3fb1dc80eb9fd7c59da21872d3?source=copy_link)


<!-- Give a quick summary of the implementation details, provide design
justifications if necessary -->
## Implementation description
Introduces an 'additional_info' field to the intake form process for
both participants and volunteers. Updates backend to store and process
this field, including database migration, API documentation, and unit
tests. Adds a new frontend form component and integrates it into the
intake flow, updating type definitions and step logic accordingly.


<!-- What should the reviewer do to verify your changes? Describe
expected results and include screenshots when appropriate -->
## Steps to test
1. Sign in and fill out intake form 
2. At the very end of the intake verify that you can reach the
"Additional Info" page (can be left empty)
3. Submit and verify the change is applied in your `users_data` table


<!-- Draw attention to the substantial parts of your PR or anything
you'd like a second opinion on -->
## What should reviewers focus on?
* In `backend/app/services/implementations/intake_form_processor.py`
line 84 let me know if a separate processor function should be written.
I saw that most of the questions did have processor functions but since
this page only is a free written input text box there isn't much logic
to abstact, but I'm not against writing one either


## Checklist
- [ ] My PR name is descriptive and in imperative tense
- [ ] My commit messages are descriptive and in imperative tense. My
commits are atomic and trivial commits are squashed or fixup'd into
non-trivial commits
- [ ] I have run the appropriate linter(s)
- [ ] I have requested a review from the PL, as well as other devs who
have background knowledge on this PR or who will be building on top of
this PR