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/settings/exceptions/domain-check-exception.php

@@ -0,0 +1,32 @@
+<?php
+
+namespace DeliciousBrains\WP_Offload_Media\Settings\Exceptions;
+
+use Exception;
+use ReflectionClass;
+
+class Domain_Check_Exception extends Exception {
+
+	/**
+	 * @var string Relative path for dbrains link
+	 */
+	protected $more_info = '/wp-offload-media/doc/assets-pull-domain-check-errors/';
+
+	/**
+	 * Get the exception name in key form.
+	 */
+	public function get_key(): string {
+		$class = new ReflectionClass( $this );
+
+		return strtolower( $class->getShortName() );
+	}
+
+	/**
+	 * Get the relative URL to a help document for this exception.
+	 *
+	 * @return string
+	 */
+	public function more_info(): string {
+		return $this->more_info;
+	}
+}

classes/settings/exceptions/http-response-exception.php

@@ -0,0 +1,6 @@
+<?php
+
+namespace DeliciousBrains\WP_Offload_Media\Settings\Exceptions;
+
+class HTTP_Response_Exception extends Domain_Check_Exception {
+}

classes/settings/exceptions/invalid-response-code-exception.php

@@ -0,0 +1,6 @@
+<?php
+
+namespace DeliciousBrains\WP_Offload_Media\Settings\Exceptions;
+
+class Invalid_Response_Code_Exception extends Domain_Check_Exception {
+}

classes/settings/exceptions/invalid-response-type-exception.php

@@ -0,0 +1,6 @@
+<?php
+
+namespace DeliciousBrains\WP_Offload_Media\Settings\Exceptions;
+
+class Invalid_Response_Type_Exception extends Domain_Check_Exception {
+}

classes/settings/exceptions/malformed-query-string-exception.php

@@ -0,0 +1,6 @@
+<?php
+
+namespace DeliciousBrains\WP_Offload_Media\Settings\Exceptions;
+
+class Malformed_Query_String_Exception extends Domain_Check_Exception {
+}

classes/settings/exceptions/malformed-response-exception.php

@@ -0,0 +1,6 @@
+<?php
+
+namespace DeliciousBrains\WP_Offload_Media\Settings\Exceptions;
+
+class Malformed_Response_Exception extends Domain_Check_Exception {
+}

classes/settings/exceptions/s3-bucket-origin-exception.php

@@ -0,0 +1,6 @@
+<?php
+
+namespace DeliciousBrains\WP_Offload_Media\Settings\Exceptions;
+
+class S3_Bucket_Origin_Exception extends Domain_Check_Exception {
+}

classes/settings/exceptions/signature-verification-exception.php

@@ -0,0 +1,6 @@
+<?php
+
+namespace DeliciousBrains\WP_Offload_Media\Settings\Exceptions;
+
+class Signature_Verification_Exception extends Domain_Check_Exception {
+}

classes/settings/exceptions/ssl-connection-exception.php

@@ -0,0 +1,6 @@
+<?php
+
+namespace DeliciousBrains\WP_Offload_Media\Settings\Exceptions;
+
+class Ssl_Connection_Exception extends Domain_Check_Exception {
+}

classes/settings/exceptions/unresolveable-hostname-exception.php

@@ -0,0 +1,6 @@
+<?php
+
+namespace DeliciousBrains\WP_Offload_Media\Settings\Exceptions;
+
+class Unresolveable_Hostname_Exception extends Domain_Check_Exception {
+}