Add LICENSE file

[renarin-kholin]

This repository has no license, meaning it defaults to standard copyright:
no one outside the org can legally reuse, modify, or redistribute this code
despite it being public. Fixing this org-wide.

Adding an MIT License to bring this in line with the org standard (status,
bit-by-design, techsig, headsup already use MIT).

Copyright holder: AISSMS IOIT ACM Student Chapter

Action items:

• Add LICENSE file with MIT text, copyright line:
  Copyright (c) 2026 AISSMS IOIT ACM Student Chapter
• Update README license badge/section if present

MIT is the org standard going forward for all chapter repos unless there's
a specific technical reason for an exception. Flag in this issue if this
repo has such a reason, otherwise this will be merged as-is.