chore: create release workflows to publish repo to Maven Central

[sasirekha3]

Release Workflows

Step	Action	Details
Prerequisites	Create Sonatype Account	Register at oss.sonatype.org
	Generate GPG Key	This was generated for us
	Configure GitHub Secrets	Add AWS Secrets Manager ARNs to repository secrets
AWS Secrets	MAVEN_CENTRAL_USERNAME_SECRET_ARN	Fetch from AWS Secrets Manager
	MAVEN_CENTRAL_PASSWORD_SECRET_ARN	Fetch from AWS Secrets Manager
	SIGNING_KEY_SECRET_ARN	Base64 encoded GPG private key (gpg --export-secret-keys --armor KEY_ID | base64)
	SIGNING_PASSWORD_SECRET_ARN	GPG key passphrase
Build Config	Publishing Plugin	maven-publish with POM metadata
	Signing	Automatic signing of all publications
	Credentials	MAVEN_CENTRAL_USERNAME_SECRET_ARN → ORG_GRADLE_PROJECT_sonatypeUsername MAVEN_CENTRAL_PASSWORD_SECRET_ARN → ORG_GRADLE_PROJECT_sonatypePassword
	Repository	https://aws.oss.sonatype.org/service/local/staging/deploy/maven2/
Release Process	Pre-release	Run pre_release.yml workflow to create version PR
	Release	Run release.yml workflow to build, sign, and publish to Maven Central
	Post-release	Run post_release.yml workflow to bump version for next development cycle

Overview

Adds automated release workflows to publish the AWS OpenTelemetry Android library to Maven Central, replacing the previous Swift-focused release process.

Changes Made

GitHub Workflows (3 files)

• pre_release.yml: Creates version update PRs, reads version from gradle.properties instead of Info.plist
• release.yml: Builds, signs, and publishes to Maven Central with secure credential management
• post_release.yml: Bumps version for next development cycle using gradle.properties

Build Configuration

• core/build.gradle.kts: Added Maven publishing configuration with POM metadata, signing, and Sonatype repository setup

Key Features

• Secure Credentials: Uses AWS Secrets Manager for Maven Central and GPG signing credentials
• Automated Signing: GPG signs all artifacts before publishing
• Version Management: Automated version bumping and branch management
• Android-Specific: Proper JDK 17 and Android SDK setup for CI builds

Required Setup

• Sonatype OSSRH account and GPG signing key
• AWS Secrets Manager entries for credentials
• GitHub repository secrets configured with AWS ARNs

---

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