docs: add GitHub Sponsors FUNDING.yml and consulting CTA

- Add .github/FUNDING.yml to enable the Sponsor button on GitHub
- Add Support section to README with sponsor badge and consulting link

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: Justin Bannister

.github/FUNDING.yml

@@ -0,0 +1,2 @@
+github: [Swevo]
+custom: ["https://solidqualitysolutions.com/"]

README.md

@@ -82,6 +82,14 @@ var pipeline = new ResiliencePipelineBuilder<HttpResponseMessage>()
 | Sliding window | ❌ | `AddSlidingWindowRateLimiter(permits, window)` |
 | Token bucket | ❌ | `AddTokenBucketRateLimiter(capacity, perPeriod, period)` |
 
+## Support
+
+If PollyRateLimiter simplifies your rate limiting setup, consider supporting the project:
+
+[![Sponsor](https://img.shields.io/badge/Sponsor-%E2%9D%A4-pink?logo=github)](https://github.com/sponsors/Swevo)
+
+> 💼 **Need .NET resilience help?** Visit [solidqualitysolutions.com](https://solidqualitysolutions.com/) for consulting and architecture services.
+
 ## License
 
 MIT