Add checksum for latest artifact to metadata file (#116)

*Issue #, if available:*
Same change as this
[PR](aws-observability/aws-otel-python-instrumentation#289)

Example: [Release
Note](https://github.com/harrryr/aws-otel-js-instrumentation/releases/tag/v)

*Testing*
Workflow run:
https://github.com/harrryr/aws-otel-js-instrumentation/actions/runs/12384515024
Verified that the .sha256 has the correct content and running `shasum -a
256 -c <artifact_name>.sha256` returns the output `<artifact_name>: OK`

By submitting this pull request, I confirm that you can use, modify,
copy, and redistribute this contribution, under the terms of your
choice.

Author: harrryr

.github/workflows/release-build.yml

@@ -14,6 +14,7 @@ env:
   RELEASE_PRIVATE_REPOSITORY: 020628701572.dkr.ecr.us-west-2.amazonaws.com/adot-autoinstrumentation-node
   RELEASE_PRIVATE_REGISTRY: 020628701572.dkr.ecr.us-west-2.amazonaws.com
   PACKAGE_NAME: aws-distro-opentelemetry-node-autoinstrumentation
+  ARTIFACT_NAME: aws-aws-distro-opentelemetry-node-autoinstrumentation-${{ github.event.inputs.version }}.tgz 
 
 permissions:
   id-token: write
@@ -86,6 +87,11 @@ jobs:
           tags: |
             ${{ env.RELEASE_PRIVATE_REPOSITORY }}:v${{ github.event.inputs.version }}
 
+      - name: Get SHA256 checksum of release artifact
+        id: get_sha256
+        run: |
+          shasum -a 256 aws-distro-opentelemetry-node-autoinstrumentation/${{ env.ARTIFACT_NAME }} | sed "s|aws-distro-opentelemetry-node-autoinstrumentation/||" > ${{ env.ARTIFACT_NAME }}.sha256
+    
       # Publish to GitHub releases
       - name: Create GH release
         id: create_release
@@ -96,7 +102,8 @@ jobs:
              --title "Release v${{ github.event.inputs.version }}" \
              --draft \
              "v${{ github.event.inputs.version }}" \
-             aws-distro-opentelemetry-node-autoinstrumentation/aws-aws-distro-opentelemetry-node-autoinstrumentation-${{ github.event.inputs.version }}.tgz
+             aws-distro-opentelemetry-node-autoinstrumentation/${{ env.ARTIFACT_NAME }} \
+             ${{ env.ARTIFACT_NAME }}.sha256
 
       # Publish to npm
       - name: Publish to npm

README.md

@@ -44,3 +44,9 @@ This project ensures compatibility with the following supported NodeJS versions:
 ### Note on Amazon CloudWatch Application Signals
 
 [Amazon CloudWatch Application Signals](https://docs.aws.amazon.com/AmazonCloudWatch/latest/monitoring/CloudWatch-Application-Monitoring-Sections.html) components are designed to seamlessly work with all library instrumentations offered by [OpenTelemetry NodeJS auto-instrumentation](https://github.com/open-telemetry/opentelemetry-js-contrib/blob/main/metapackages/auto-instrumentations-node/README.md). While upstream OpenTelemetry NodeJS instrumentations are in beta, Application Signals components are stable, production ready and have also been tested for popular libraries/frameworks such as `ExpressJS, AWS SDK for JavaScript V3, and others`. We will prioritize backward compatibility for Application Signals components, striving to ensure that they remain functional even in the face of potential breaking changes introduced by OpenTelemetry upstream libraries. Please [raise an issue](https://github.com/aws-observability/aws-otel-js-instrumentation/blob/main/CONTRIBUTING.md#reporting-bugsfeature-requests) if you notice Application Signals doesn't work for a particular OpenTelemetry supported library.
+
+## Checksum Verification
+
+Artifacts released will include a `.sha256` file for checksum verification starting from v0.4.0
+To verify, run the command `shasum -a 256 -c <artifact_name>.sha256`
+It should return the output `<artifact_name>: OK` if the validation is successful