Add documentation for DetourCrowd

[arturkamieniecki]

Change summary

Submission Checklist:

• Descriptive active voice - Do descriptive sentences have a clear subject and action verb?
• Answer the question at hand - Does the documentation answer a what, why, how, or where type of question?
• Consistency - Does the content consistently follow the Style Guide?
• Help the user - Does the documentation show the user something meaningful?
• All commits are signed off - Do all commits have a Signed-off-by line at the end, with an email verified by GitHub?

Implementation link

o3de/o3de#19707