feat(plan_limits): add Helm limits to API and UI

What does this MR do and why?

This MR adds the maximum storage size for Helm charts to the admin UI, the instance-configuration page, and the API.

🛠 with ❤ at Siemens

Closes #344925 (closed)

/cc @fh1ch

Screenshots or screen recordings

admin UI	instance config

How to set up and validate locally

Admin UI

1. Visit the admin area at http://127.0.0.1:3000/admin/application_settings/ci_cd#js-package-settings
2. Edit the Maximum Helm chart file size in bytes for some plan
3. Click Save <plan> size limits
4. Check the updated value

Instance configuration

Visit the instance-configuration page at http://127.0.0.1:3000/help/instance_configuration#package-registry

API

Send the corresponding API requests as documented here:

curl --header "PRIVATE-TOKEN: <your_access_token>" "http://127.0.0.1:3000/api/v4/application/plan_limits"
curl --request PUT --header "PRIVATE-TOKEN: <your_access_token>" "http://127.0.0.1:3000//api/v4/application/plan_limits?plan_name=default&helm_max_file_size=314159265"

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• I have evaluated the MR acceptance checklist for this MR.