Deprecating stale apps

## Description

It seems some apps are no longer needed or useful moving forward:

1. [`codeforafrica`](https://cfa.dev.codeforafrica.org/): This never went to PROD and with the launch of Plus alliance, it feels like it never will.
2. `vpnmanager`: It was useful at some point but but I don't think it's needed moving forward and it's something that can easily redesign and recreated from scratch if needed. Lets us know @cfabako / @koechkevin if this is incorrect.
3. [`climatemappedafrica`](https://climatemapped-africa.dev.codeforafrica.org/): This never went to PROD and not sure if there are any plans to do so. Over to you @elric-wamugu.

With the way (npm?) security compromises and issues are popping up everyday, we should make sure we're "travelling light" moving forward.

The issue identifies codeforafrica, vpnmanager, and climatemappedafrica as potentially stale apps, but names no files, tests, or entry points. First confirm with the mentioned stakeholders which apps should be retired, then inspect the repository structure and dependency configuration. Done means the agreed stale apps and their related dependencies are removed without affecting the remaining apps.

Written by the indexing model from the issue text.