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

vendor/Aws3/JmesPath/SyntaxErrorException.php

@@ -0,0 +1,25 @@
+<?php
+
+namespace DeliciousBrains\WP_Offload_Media\Aws3\JmesPath;
+
+/**
+ * Syntax errors raise this exception that gives context
+ */
+class SyntaxErrorException extends \InvalidArgumentException
+{
+    /**
+     * @param string $expectedTypesOrMessage Expected array of tokens or message
+     * @param array  $token                  Current token
+     * @param string $expression             Expression input
+     */
+    public function __construct($expectedTypesOrMessage, array $token, $expression)
+    {
+        $message = \sprintf("Syntax error at character %d\n", \max($token['pos'], 0)) . $expression . "\n" . \str_repeat(' ', \max($token['pos'], 0)) . "^\n";
+        $message .= !\is_array($expectedTypesOrMessage) ? $expectedTypesOrMessage : $this->createTokenMessage($token, $expectedTypesOrMessage);
+        parent::__construct($message);
+    }
+    private function createTokenMessage(array $token, array $valid)
+    {
+        return \sprintf('Expected one of the following: %s; found %s "%s"', \implode(', ', \array_keys($valid)), $token['type'], $token['value']);
+    }
+}