docs: move support terms to .github/SUPPORT.md (#3165)

Use GitHub's standard SUPPORT.md community file: a Getting help section
(Discussions, issues, SECURITY.md) plus the Paid support terms that were
in SUPPORT-SPONSORSHIP.md.

Claude-Session: https://claude.ai/code/session_01QKDYQr53zNKkR7nif2CAAq

Author: vishr

SUPPORT-SPONSORSHIP.md .github/SUPPORT.mdSUPPORT-SPONSORSHIP.md renamed to .github/SUPPORT.md

@@ -1,23 +1,32 @@
-# Echo Support Sponsorship Terms
+# Support
 
-These terms apply to the Support tier on [GitHub Sponsors](https://github.com/sponsors/labstack), provided by LabStack LLC.
+## Getting help
 
-## What you get
+- **Questions:** ask in [GitHub Discussions](https://github.com/labstack/echo/discussions).
+- **Bugs:** open an [issue](https://github.com/labstack/echo/issues) with a minimal example that reproduces the problem.
+- **Security vulnerabilities:** report them privately, as described in [SECURITY.md](../SECURITY.md). Do not open a public issue.
+- **Documentation:** [echo.labstack.com](https://echo.labstack.com).
+
+## Paid support
+
+Companies running Echo in production can get support through the Support tier on [GitHub Sponsors](https://github.com/sponsors/labstack), provided by LabStack LLC.
+
+### What you get
 
 - Everything in the Business tier.
 - We aim to reply to your issues and questions within 2 business days.
 - A named contact for security questions, and a heads-up on scheduled security release dates.
 - A written summary of Echo's published support periods for the versions you use.
 - Help answering SBOM and vulnerability questions for your compliance reviews.
 
-## Terms
+### Terms
 
 1. **Best effort.** Support is provided on a best-effort basis. Response times are goals, not guarantees.
-2. **Security notice.** Advance notice covers only the planned release date and the affected version lines. Vulnerability details and fixes are published publicly, for everyone, at release time, following coordinated disclosure. See [SECURITY.md](./SECURITY.md).
-3. **Support statements.** Support-period summaries restate Echo's public policy in [ROADMAP.md](./ROADMAP.md) and [SECURITY.md](./SECURITY.md), which may change. They are not a warranty.
-4. **No warranty.** Echo is provided under the [MIT License](./LICENSE), "as is". Sponsorship does not change that.
+2. **Security notice.** Advance notice covers only the planned release date and the affected version lines. Vulnerability details and fixes are published publicly, for everyone, at release time, following coordinated disclosure. See [SECURITY.md](../SECURITY.md).
+3. **Support statements.** Support-period summaries restate Echo's public policy in [ROADMAP.md](../ROADMAP.md) and [SECURITY.md](../SECURITY.md), which may change. They are not a warranty.
+4. **No warranty.** Echo is provided under the [MIT License](../LICENSE), "as is". Sponsorship does not change that.
 5. **Liability.** LabStack LLC's total liability is limited to the sponsorship fees paid in the previous 3 months.
 6. **Billing.** Billed through GitHub Sponsors under GitHub's terms, or invoiced by LabStack LLC. You can cancel anytime; past months are not refunded.
 7. **Changes.** These terms may be updated. The current version is always in this file.
 
-Questions: [v@labstack.com](mailto:v@labstack.com)
+Questions about paid support: [v@labstack.com](mailto:v@labstack.com)