<!-- Clearly explain the need for these changes: -->
Nick wants others to be able to write tests besides Nick
### Changes 🏗️
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- Fixes various import errors across the docs to fix dead links
- Adds Docs for making and debugging your own tests
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Co-authored-by: Swifty <craigswift13@gmail.com>
Restructuring the Repo to make it clear the difference between classic autogpt and the autogpt platform:
* Move the "classic" projects `autogpt`, `forge`, `frontend`, and `benchmark` into a `classic` folder
* Also rename `autogpt` to `original_autogpt` for absolute clarity
* Rename `rnd/` to `autogpt_platform/`
* `rnd/autogpt_builder` -> `autogpt_platform/frontend`
* `rnd/autogpt_server` -> `autogpt_platform/backend`
* Adjust any paths accordingly
