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/Aws/EndpointV2/EndpointProviderV2.php

@@ -0,0 +1,56 @@
+<?php
+
+namespace DeliciousBrains\WP_Offload_Media\Aws3\Aws\EndpointV2;
+
+use DeliciousBrains\WP_Offload_Media\Aws3\Aws\EndpointV2\Ruleset\Ruleset;
+use DeliciousBrains\WP_Offload_Media\Aws3\Aws\Exception\UnresolvedEndpointException;
+use DeliciousBrains\WP_Offload_Media\Aws3\Aws\LruArrayCache;
+/**
+ * Given a service's Ruleset and client-provided input parameters, provides
+ * either an object reflecting the properties of a resolved endpoint,
+ * or throws an error.
+ */
+class EndpointProviderV2
+{
+    /** @var Ruleset */
+    private $ruleset;
+    /** @var LruArrayCache */
+    private $cache;
+    public function __construct(array $ruleset, array $partitions)
+    {
+        $this->ruleset = new Ruleset($ruleset, $partitions);
+        $this->cache = new LruArrayCache(100);
+    }
+    /**
+     * @return Ruleset
+     */
+    public function getRuleset()
+    {
+        return $this->ruleset;
+    }
+    /**
+     * Given a Ruleset and input parameters, determines the correct endpoint
+     * or an error to be thrown for a given request.
+     *
+     * @return RulesetEndpoint
+     * @throws UnresolvedEndpointException
+     */
+    public function resolveEndpoint(array $inputParameters)
+    {
+        $hashedParams = $this->hashInputParameters($inputParameters);
+        $match = $this->cache->get($hashedParams);
+        if (!\is_null($match)) {
+            return $match;
+        }
+        $endpoint = $this->ruleset->evaluate($inputParameters);
+        if ($endpoint === \false) {
+            throw new UnresolvedEndpointException('Unable to resolve an endpoint using the provider arguments: ' . \json_encode($inputParameters));
+        }
+        $this->cache->set($hashedParams, $endpoint);
+        return $endpoint;
+    }
+    private function hashInputParameters($inputParameters)
+    {
+        return \md5(\serialize($inputParameters));
+    }
+}