Add per-user daily rate limit on project and group creation

What does this MR do and why?

• Add per-user daily rate limit of 200/day on project and group creation to prevent abusive behaviour.

Screenshots or recordings

Groups API

Projects API

Steps to reproduce

1. Enable the feature flag

Feature.enable(:namespace_create_rate_limit)

2. Configure the rate limits by navigating to Admin > Settings > Network > Projects API rate limits. Update the value to 2 for now.

3. Restart GDK

4. Try to create multiple projects either using the UI or the API:

curl --request POST \
  --header "PRIVATE-TOKEN: <your_token>" \
  --header "Content-Type: application/json" \
  --data '{"name": "Test <X>"}' \
  "<GDK>/api/v4/projects"

MR acceptance checklist

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Resolves #601717 (comment 3550482742)