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/Exception/RequestException.php

@@ -0,0 +1,111 @@
+<?php
+
+namespace DeliciousBrains\WP_Offload_Media\Aws3\GuzzleHttp\Exception;
+
+use DeliciousBrains\WP_Offload_Media\Aws3\GuzzleHttp\BodySummarizer;
+use DeliciousBrains\WP_Offload_Media\Aws3\GuzzleHttp\BodySummarizerInterface;
+use DeliciousBrains\WP_Offload_Media\Aws3\Psr\Http\Client\RequestExceptionInterface;
+use DeliciousBrains\WP_Offload_Media\Aws3\Psr\Http\Message\RequestInterface;
+use DeliciousBrains\WP_Offload_Media\Aws3\Psr\Http\Message\ResponseInterface;
+/**
+ * HTTP Request exception
+ */
+class RequestException extends TransferException implements RequestExceptionInterface
+{
+    /**
+     * @var RequestInterface
+     */
+    private $request;
+    /**
+     * @var ResponseInterface|null
+     */
+    private $response;
+    /**
+     * @var array
+     */
+    private $handlerContext;
+    public function __construct(string $message, RequestInterface $request, ?ResponseInterface $response = null, ?\Throwable $previous = null, array $handlerContext = [])
+    {
+        // Set the code of the exception if the response is set and not future.
+        $code = $response ? $response->getStatusCode() : 0;
+        parent::__construct($message, $code, $previous);
+        $this->request = $request;
+        $this->response = $response;
+        $this->handlerContext = $handlerContext;
+    }
+    /**
+     * Wrap non-RequestExceptions with a RequestException
+     */
+    public static function wrapException(RequestInterface $request, \Throwable $e) : RequestException
+    {
+        return $e instanceof RequestException ? $e : new RequestException($e->getMessage(), $request, null, $e);
+    }
+    /**
+     * Factory method to create a new exception with a normalized error message
+     *
+     * @param RequestInterface             $request        Request sent
+     * @param ResponseInterface            $response       Response received
+     * @param \Throwable|null              $previous       Previous exception
+     * @param array                        $handlerContext Optional handler context
+     * @param BodySummarizerInterface|null $bodySummarizer Optional body summarizer
+     */
+    public static function create(RequestInterface $request, ?ResponseInterface $response = null, ?\Throwable $previous = null, array $handlerContext = [], ?BodySummarizerInterface $bodySummarizer = null) : self
+    {
+        if (!$response) {
+            return new self('Error completing request', $request, null, $previous, $handlerContext);
+        }
+        $level = (int) \floor($response->getStatusCode() / 100);
+        if ($level === 4) {
+            $label = 'Client error';
+            $className = ClientException::class;
+        } elseif ($level === 5) {
+            $label = 'Server error';
+            $className = ServerException::class;
+        } else {
+            $label = 'Unsuccessful request';
+            $className = __CLASS__;
+        }
+        $uri = \DeliciousBrains\WP_Offload_Media\Aws3\GuzzleHttp\Psr7\Utils::redactUserInfo($request->getUri());
+        // Client Error: `GET /` resulted in a `404 Not Found` response:
+        // <html> ... (truncated)
+        $message = \sprintf('%s: `%s %s` resulted in a `%s %s` response', $label, $request->getMethod(), $uri->__toString(), $response->getStatusCode(), $response->getReasonPhrase());
+        $summary = ($bodySummarizer ?? new BodySummarizer())->summarize($response);
+        if ($summary !== null) {
+            $message .= ":\n{$summary}\n";
+        }
+        return new $className($message, $request, $response, $previous, $handlerContext);
+    }
+    /**
+     * Get the request that caused the exception
+     */
+    public function getRequest() : RequestInterface
+    {
+        return $this->request;
+    }
+    /**
+     * Get the associated response
+     */
+    public function getResponse() : ?ResponseInterface
+    {
+        return $this->response;
+    }
+    /**
+     * Check if a response was received
+     */
+    public function hasResponse() : bool
+    {
+        return $this->response !== null;
+    }
+    /**
+     * Get contextual information about the error from the underlying handler.
+     *
+     * The contents of this array will vary depending on which handler you are
+     * using. It may also be just an empty array. Relying on this data will
+     * couple you to a specific handler, but can give more debug information
+     * when needed.
+     */
+    public function getHandlerContext() : array
+    {
+        return $this->handlerContext;
+    }
+}