refactor: remove React imports to specified files and delete unused r…

[kianflorendo]

…oute

✨ What’s New?

1. Removes unused import React from react declarations across 10 different frontend components.
2. Deletes the legacy, unused frontend/src/app/api/templates/route.ts API route

📷 Screenshots (IMPORTANT)

N/A - This is a purely code-level cleanup/refactor with no graphical interface changes.

🔗 Related Issues

Closes #118
Closes #108

✅ Checklist

• [/ ] Code follows project conventions.
• [/ ] Unused code, variables, and console logs have been removed.
• [/ ] Code compiles and runs without errors.
• Build and tests succeeds locally.
• [/ ] Assigned at least one reviewer.

[geraldsberongoy]

lgtm!