feat: Improve Survey builder and viewer UI/UX

[antoniocapelo]

This PR aims to improve the UX and UI of the existing application, as well as to implement some features that were listed in the Readme file.

I also added a notes.md file that acted as my personal todo list and a place to jot down ideas as I went along the exercise.

Key Changes

• Unified the create and edit survey forms into a single component.
• Added a new search feature for surveys.
• Added layout with header and man section.
• Implemented a table view for the homepage (with persistence).
• Enhanced survey creation and viewing UX, including a progress bar, loading indicators, and error summary.
• Added a "preview" mode for surveys.
• Improved form validation using Zod schemas and created a reusable validation hook.
• Added "Optional" indicators for form fields and removed asterisks.
• Various UI tweaks, bug fixes, and code cleanups.

What's not done

A list of things I could work on but decided to not prioritize to keep the exercise duration contained:

• Consistent app navigation layout (breadcrumbs, back button positioning, etc)
• Re-think survey creation actions (maybe make the actions "sticky" and not have to scroll down to see them)
• mouse interactions on table and cards (left click on row/card navigate to survey, right click pops up available actions)

Demo

I've made a Loom demoing the main changes and I'm hosting the app at https://survey-builder.capelo.me/.