feat: add AEM client package

[holtvogt]

Summary

Introduces @adobe/spacecat-shared-aem-client. A client library for interacting with AEM Cloud Service APIs.

Features

• Fragment Management: CRUD operations for content fragments
• Fragment Versioning: Create versions of content fragments
• Fragment Tagging: CRUD operations for tags on content fragments

Highlights

• IMS authentication via @adobe/spacecat-shared-ims-client
• Builder pattern for flexible capability composition
• Comprehensive error handling with typed errors (authentication, conflict, precondition-failed, etc.)

Usage

import { AemClientBuilder } from '@adobe/spacecat-shared-aem-client';

const { management, versioning, tagging } = AemClientBuilder.create({ site, env, log })
  .withManagement()
  .withVersioning()
  .withTagging()
  .build();

const fragment = await management.getFragment('/content/dam/my-project/fragment');

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[Copilot]

Pull request overview

This PR introduces a new client library @adobe/spacecat-shared-aem-client for interacting with Adobe Experience Manager (AEM) Cloud Service APIs. The library provides a builder pattern for flexible composition of client capabilities including fragment management, versioning, and tagging.

Key changes include:

• Builder pattern implementation for flexible client instantiation
• Comprehensive error hierarchy with typed errors for different HTTP status codes
• IMS authentication integration for secure API access

Reviewed changes

Copilot reviewed 36 out of 37 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
package.json	Package configuration with dependencies on IMS client and shared utils
README.md	Comprehensive usage documentation with examples for all capabilities
src/index.js	Main entry point exporting builder, errors, and site management classes
src/index.d.ts	TypeScript definitions for all exported classes and interfaces
src/aem-client-base.js	Base client with authentication and HTTP request handling
src/aem-client-builder.js	Builder pattern for composing client capabilities
src/errors/*.js	Error class hierarchy for typed error handling
src/sites/fragment-*.js	Fragment management, versioning, and tagging implementations
src/sites/constants.js	API endpoint constants
test/**/*.test.js	Comprehensive test coverage for all modules
Configuration files	Standard project setup including ESLint, Mocha, NYC, and semantic-release

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[github-actions]

This PR will trigger a minor release when merged.