Update README with end-of-support timeline and add migration links (#504)

Author: jj22ee

README.md

@@ -1,13 +1,30 @@
 ![Test](https://github.com/aws/aws-xray-sdk-go/workflows/Test/badge.svg)
 [![Go Report Card](https://goreportcard.com/badge/github.com/aws/aws-xray-sdk-go)](https://goreportcard.com/report/github.com/aws/aws-xray-sdk-go)
 
-### :mega: OpenTelemetry Go with AWS X-Ray
+# AWS X-Ray SDK for Go
+
+## :mega: Upcoming Maintenance Mode on February 25, 2026
+
+[The AWS X-Ray SDKs will enter maintenance mode on **`February 25, 2026`**][xray-sdk-daemon-timeline]. During maintenance mode, the X-Ray SDKs and Daemon will only receive critical bug fixes and security updates, and will not be updated to support new features.
+
+We recommend that you migrate to [AWS Distro for OpenTelemetry (ADOT) or OpenTelemetry Instrumentation][xray-otel-migration-docs] to generate traces (through manual or zero-code instrumentation) from your application and send them to AWS X-Ray. OpenTelemetry is the industry-wide standard for tracing instrumentation and observability. It has a large open-source community for support and provides more instrumentations and updates. By adopting an OpenTelemetry solution, developers can leverage the latest services and innovations from AWS CloudWatch.
+
+## :mega: End-of-Support on February 25, 2027
+
+[The AWS X-Ray SDKs will reach end-of-support on **`February 25, 2027`**][xray-sdk-daemon-timeline]. After end-of-support, the X-Ray SDKs will no longer receive updates or releases. Previously published releases will continue to be available via public package managers and the source code will remain on GitHub.
+
+[xray-otel-migration-docs]: https://docs.aws.amazon.com/xray/latest/devguide/xray-sdk-migration.html
+[xray-sdk-daemon-timeline]: https://docs.aws.amazon.com/xray/latest/devguide/xray-daemon-eos.html
+
+-------------------------------------
+
+### OpenTelemetry Go with AWS X-Ray
 
 AWS X-Ray supports using OpenTelemetry Go and the AWS Distro for OpenTelemetry (ADOT) Collector to instrument your application and send trace data to X-Ray. The OpenTelemetry SDKs are an industry-wide standard for tracing instrumentation. They provide more instrumentations and have a larger community for support, but may not have complete feature parity with the X-Ray SDKs. See [choosing between the ADOT and X-Ray SDKs](https://docs.aws.amazon.com/xray/latest/devguide/xray-instrumenting-your-app.html#xray-instrumenting-choosing) for more help with choosing between the two.
 
 If you want additional features when tracing your Go applications, please [open an issue on the OpenTelemetry Go Instrumentation repository](https://github.com/open-telemetry/opentelemetry-go-contrib/issues/new?title=X-Ray%20Compatible%20Feature%20Request).
 
-# AWS X-Ray SDK for Go
+-------------------------------------
 
 ![Screenshot of the AWS X-Ray console](/images/example.png?raw=true)