feat: custom S3 endpoint to use third party storage services

[sebiweise]

What does this PR do?

I´ve added the available S3 environment vars to .env.example.
Also added the ability to define a custom S3 endpoint to use Third Party S3 compatible storage services like StorJ.

How should this be tested?

Register for StorJ or another S3 storage provider
Define all environment vars:

• S3_ENDPOINT e.g. https://gateway.storjshare.io
• S3_REGION e.g. eu1
• S3_ACCESS_KEY
• S3_SECRET_KEY
• S3_BUCKET_NAME

Checklist

• Upload profile picture
• Upload picture question image
• Upload files in file upload question

Required

• Filled out the "How to test" section in this PR
• Read How we Code at Formbricks
• Self-reviewed my own code
• Commented on my code in hard-to-understand bits
• Ran pnpm build
• Checked for warnings, there are none
• Removed all console.logs
• Merged the latest changes from main onto my branch with git pull origin main
• My changes don't cause any responsiveness issues

Appreciated

• Updated the Formbricks Docs if changes were necessary

[vercel]

@sebiweise is attempting to deploy a commit to the formbricks Team on Vercel.

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[github-actions]

Thank you for following the naming conventions for pull request titles! 🙏

[mattinannt]

@sebiweise I would like to make changes to the PR but unfortunately I'm not able to push them. Did you allow maintainers to make changes?

[sebiweise]

@sebiweise I would like to make changes to the PR but unfortunately I'm not able to push them. Did you allow maintainers to make changes?

I don´t really know how to do this, can you tell what I have to change so that you can push changes?

[mattinannt]

When creating the pull request you can select this option. I'm not sure if you can also change this setting afterwards. If it's enabled we should be able to see this in the info-bar on the right:

---

Update: you might be able to just check it:

[sebiweise]

Unfortunately I don´t have this options.
I tried to recreate the PR but even then I don´t have the option to enable maintainer edit.

[sebiweise]

I think thats the problem: https://github.com/orgs/community/discussions/5634#discussion-3570791

[sebiweise]

Fixed it, you should be able to edit now.

[mattinannt]

@sebiweise Nice, it's working now, thank you ☺️🚀💪
I changed a few smaller things and merge it now 🔥

Thanks a lot for your contribution 😊