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/GuzzleHttp/Promise/Create.php

@@ -0,0 +1,68 @@
+<?php
+
+declare (strict_types=1);
+namespace DeliciousBrains\WP_Offload_Media\Aws3\GuzzleHttp\Promise;
+
+final class Create
+{
+    /**
+     * Creates a promise for a value if the value is not a promise.
+     *
+     * @param mixed $value Promise or value.
+     */
+    public static function promiseFor($value) : PromiseInterface
+    {
+        if ($value instanceof PromiseInterface) {
+            return $value;
+        }
+        // Return a Guzzle promise that shadows the given promise.
+        if (\is_object($value) && \method_exists($value, 'then')) {
+            $wfn = \method_exists($value, 'wait') ? [$value, 'wait'] : null;
+            $cfn = \method_exists($value, 'cancel') ? [$value, 'cancel'] : null;
+            $promise = new Promise($wfn, $cfn);
+            $value->then([$promise, 'resolve'], [$promise, 'reject']);
+            return $promise;
+        }
+        return new FulfilledPromise($value);
+    }
+    /**
+     * Creates a rejected promise for a reason if the reason is not a promise.
+     * If the provided reason is a promise, then it is returned as-is.
+     *
+     * @param mixed $reason Promise or reason.
+     */
+    public static function rejectionFor($reason) : PromiseInterface
+    {
+        if ($reason instanceof PromiseInterface) {
+            return $reason;
+        }
+        return new RejectedPromise($reason);
+    }
+    /**
+     * Create an exception for a rejected promise value.
+     *
+     * @param mixed $reason
+     */
+    public static function exceptionFor($reason) : \Throwable
+    {
+        if ($reason instanceof \Throwable) {
+            return $reason;
+        }
+        return new RejectionException($reason);
+    }
+    /**
+     * Returns an iterator for the given value.
+     *
+     * @param mixed $value
+     */
+    public static function iterFor($value) : \Iterator
+    {
+        if ($value instanceof \Iterator) {
+            return $value;
+        }
+        if (\is_array($value)) {
+            return new \ArrayIterator($value);
+        }
+        return new \ArrayIterator([$value]);
+    }
+}