Feature: Adjust environment variables and deploy on Vercel

[nick-y-ito]

Overview

This PR adjusts the environment variables for deployment. Accordingly, this branch has been deployed to Vercel as a "preview" deployment.

Changes

• Only renamed the env variables *I did NOT remove the NEXT_PUBLIC_ prefix from any existing env variables because I figured out that they all have to be exposed to the client side.

Review points

• Please only check if there is no error that this PR generated.

Screen Captures

References

Notes

• I will secretly share the testing URL with the reviewers.
• After this PR is merged into development as well as the main, I will also deploy them.

Assignee Checklist:

• [x] The naming convention of the PR title is correct (See the comment at the top of this template)
• [x] The base branch is correct (See: Types of Branches)
• [x] The branch name follows the Branch Naming Conventions
• [x] The correct assignees and reviewers have been designated for this PR
• [x] The coding style follows the Coding Style Guide
• [x] All the related issues are associated with this PR
• [x] All criteria in the associated issues are met (please tick the checkboxes)
• [x] My changes do not generate new warnings or errors (especially in the console)

Reviewer Checklist:

• [ ] Double-check the "Assignee Checklist"
• [ ] The code follows the generic best practices and our Coding Style Guide
• [ ] The code is well-commented and easy to understand
• [ ] The UI changes accurately reflect the provided design

[nick-y-ito]

@kanta1207 Thank you for your review 😄