feat: add S3-compatible storage provider (MinIO, Ceph, R2, etc.)

Adds a new 'S3-Compatible Storage' provider that works with any
S3-API-compatible object storage service, including MinIO, Ceph,
Cloudflare R2, Backblaze B2, and others.

Changes:
- New provider class: classes/providers/storage/s3-compatible-provider.php
  - Provider key: s3compatible
  - Reads user-configured endpoint URL from settings
  - Uses path-style URL access (required by most S3-compatible services)
  - Supports credentials via AS3CF_S3COMPAT_ACCESS_KEY_ID /
    AS3CF_S3COMPAT_SECRET_ACCESS_KEY wp-config.php constants
  - Disables AWS-specific features (Block Public Access, Object Ownership)
- New provider SVG icons (s3compatible.svg, -link.svg, -round.svg)
- Registered provider in main plugin class with endpoint setting support
- Updated StorageProviderSubPage to show endpoint URL input for S3-compatible
- Built pro settings bundle with rollup (Svelte 4.2.19)
- Added package.json and updated rollup.config.mjs for pro-only builds

classes/providers/delivery/digitalocean-spaces-cdn.php

@@ -0,0 +1,102 @@
+<?php
+
+namespace DeliciousBrains\WP_Offload_Media\Providers\Delivery;
+
+class DigitalOcean_Spaces_CDN extends Delivery_Provider {
+
+	/**
+	 * Which storage providers does the delivery provider support, empty means all.
+	 *
+	 * @var array
+	 */
+	protected static $supported_storage_providers = array(
+		'do',
+	);
+
+	/**
+	 * @var string
+	 */
+	protected static $provider_name = 'DigitalOcean';
+
+	/**
+	 * @var string
+	 */
+	protected static $provider_short_name = 'DigitalOcean';
+
+	/**
+	 * Used in filters and settings.
+	 *
+	 * @var string
+	 */
+	protected static $provider_key_name = 'do';
+
+	/**
+	 * @var string
+	 */
+	protected static $service_name = 'Spaces CDN';
+
+	/**
+	 * @var string
+	 */
+	protected static $service_short_name = 'Spaces CDN';
+
+	/**
+	 * Used in filters and settings.
+	 *
+	 * @var string
+	 */
+	protected static $service_key_name = 'spaces-cdn';
+
+	/**
+	 * Optional override of "Provider Name" + "Service Name" for friendly name for service.
+	 *
+	 * @var string
+	 */
+	protected static $provider_service_name = 'DigitalOcean Spaces CDN';
+
+	/**
+	 * The slug for the service's quick start guide doc.
+	 *
+	 * @var string
+	 */
+	protected static $provider_service_quick_start_slug = 'digitalocean-spaces-cdn-setup';
+
+	/**
+	 * @var string
+	 */
+	protected $default_domain = 'cdn.digitaloceanspaces.com';
+
+	/**
+	 * @var string
+	 */
+	protected $console_url = 'https://cloud.digitalocean.com/spaces/';
+
+	/**
+	 * @var string
+	 */
+	protected $console_url_prefix_param = '?path=';
+
+	/**
+	 * Get the link to the provider's console.
+	 *
+	 * @param string $bucket
+	 * @param string $prefix
+	 * @param string $region
+	 *
+	 * @return string
+	 *
+	 * NOTE: DigitalOcean Spaces CDN is tied to the Space and does not have a separate means of access.
+	 */
+	public function get_console_url( string $bucket = '', string $prefix = '', string $region = '' ): string {
+		return $this->as3cf->get_storage_provider()->get_console_url( $bucket, $prefix, $region );
+	}
+
+	/**
+	 * Title to be shown for provider's console link.
+	 *
+	 * @return string
+	 */
+	public static function get_console_title(): string {
+		return _x( 'Control Panel', 'Provider console link text', 'amazon-s3-and-cloudfront' );
+	}
+}