docs: add non-AWS endpoint guidance and list Tigris as compatible

[davidmyriel]

Hey there :)! I just have two small additions to extensions/s3.mdx:

1. Adds a short "Using a non-AWS endpoint" subsection that shows the common config pattern (s3_endpoint + s3_region + credentials) for S3-compatible services, and calls out two things the current page doesn't address:

   • s3_region is required for request signing but is ignored by most non-AWS services — it isn't obvious from the options table what to put there when your service doesn't have AWS-style regions
   • s3_url_style defaults to vhost; path-style is sometimes required (e.g. MinIO)

2. Adds Tigris next to Cloudflare R2 in the existing "compatible with the S3 API" sentence lower on the page.

Let me know if you need me to adjust anything

Thanks!

[Copilot]

Pull request overview

Adds documentation to help users configure the httpfs S3 feature against S3-compatible (non-AWS) providers, and expands the list of known-compatible services.

Changes:

• Add a “Using a non-AWS endpoint” section with a common s3_endpoint + s3_region (+ optional s3_url_style) configuration pattern.
• Mention Tigris as an S3-compatible provider alongside Cloudflare R2.

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.