/**
 * Configuration loading adapters for the bootstrap phase.
 * <p>
 * Contains implementations of the {@link de.gecheckt.pdf.umbenenner.application.port.out.ConfigurationPort}
 * that load the complete {@link de.gecheckt.pdf.umbenenner.application.config.startup.StartConfiguration}
 * from external sources (e.g., properties files, environment variables).
 * <p>
 * Responsibilities:
 * <ul>
 *   <li>Load configuration from the properties file (default: config/application.properties)</li>
 *   <li>Apply environment variable precedence for sensitive values (e.g., API key)</li>
 *   <li>Construct the typed StartConfiguration object with all technical infrastructure parameters</li>
 * </ul>
 * <p>
 * These adapters bridge the outbound port contract with concrete infrastructure
 * (property file parsing, environment variable lookup) without leaking infrastructure details
 * into the application or bootstrap layers. Validation of the loaded configuration is performed
 * separately by the {@link de.gecheckt.pdf.umbenenner.adapter.out.bootstrap.validation.StartConfigurationValidator}
 * in the bootstrap phase.
 */
package de.gecheckt.pdf.umbenenner.adapter.out.configuration;