Saved Folders Feature

[laurenp-2]

Summary

This pull request implements the folder saving feature, where users can assign apartments to custom folders.

• Implemented api endpoints for the creation, renaming, and deletion of folders
• Implemented api endpoints to add and remove apartments to folders
• Implemented a frontend Folders page where users can see all their folders and the apartments saved to them
• Added a 'Save to folder' button in apartment pages

Test Plan

Screenshots of the Folders page and Save to Folder modal

Postman was used to test the api endpoints and make sure the backend worked smoothly.

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[dti-github-bot]

[diff-counting] Significant lines: 1463. This diff might be too big! Developer leads are invited to review the code.

[parsa-tehranipoor]

Super cool feature Lauren! Your backend routes look really polished and nicely organized. You followed our coding conventions really well, which made understanding your work 10x easier. The UI from the screenshots above also looks really nice. Nice job!