/**
 * Bootstrap-phase technical configuration validation.
 * <p>
 * Handles startup configuration validation as a separate step after configuration loading.
 * Validates mandatory fields, numeric ranges, URI schemes, and path existence before
 * the batch application begins. If validation fails, the application exits with code 1.
 * <p>
 * Validation concerns include:
 * <ul>
 *   <li>Mandatory field presence and non-nullness</li>
 *   <li>Numeric constraints (timeout, retry limits, page counts, character limits)</li>
 *   <li>URI validity (API base URL must be absolute with http or https scheme)</li>
 *   <li>Path existence and type (source/target folders exist and are readable, etc.)</li>
 *   <li>Path relationships (source and target folders are not the same)</li>
 * </ul>
 * <p>
 * This validation is a technical responsibility that does not belong to the application layer
 * and is distinct from configuration loading. The validator is created and invoked by the
 * bootstrap phase after configuration is loaded.
 */
package de.gecheckt.pdf.umbenenner.adapter.out.bootstrap.validation;
