chore: swagger API documentation

[MC-Knight]

What does this PR do?

This pull request aims to add swagger API documentation to knights-ecomm-be project

Description of Task to be completed?

The task completed in this pull request includes:

• setting up swagger API documentation tool in project
• adding endpoint to access swagger documentation ui

How should this be manually tested?

To manually test all the changes made in this pull request, follow these steps:

git clone -b ft-api-docs https://github.com/atlp-rwanda/knights-ecomm-be.git
cd knights-ecomm-be
npm i
npm run dev
access http://localhost:{port}/api/v1/docs

example

[elijahladdie]

Well done Joe

[aimedivin]

Good job 👍🏿

[faid-terence]

Nice Work @MC-Knight !