### Overview
This is the implementation of Code Frequency page. This feature was
mentioned on these issues: #18262, #7392.
It adds another tab to Activity page called Code Frequency. Code
Frequency tab shows additions and deletions over time since the
repository existed.
Before:
<img width="1296" alt="image"
src="https://github.com/go-gitea/gitea/assets/32161460/2603504f-aee7-4929-a8c4-fb3412a7a0f6">
After:
<img width="1296" alt="image"
src="https://github.com/go-gitea/gitea/assets/32161460/58c03721-729f-4536-a663-9f337f240963">
---
#### Features
- See additions deletions over time since repository existed
- Click on "Additions" or "Deletions" legend to show only one type of
contribution
- Use the same cache from Contributors page so that the loading of data
will be fast once it is cached by visiting either one of the pages
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Co-authored-by: Giteabot <teabot@gitea.io>
