[Refactor] Remove the Leetcode Controller

[JRS296]

Description

• Leetcode Controller ?? Why are there Delete options annol @AmanDeol7
• The only LC related thing would be through the Statistics route. We do not need controllers to "Add and Delete" badges for example.

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[AmanDeol7]

Yes, /Dijkstra/v1/leetcode endpoint is not used anywhere in the frontend. Only leetcode related api used is via the statistics endpoint. I will proceed to clean it up