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/Gcp/google/common-protos/src/Api/FieldBehavior.php

@@ -0,0 +1,115 @@
+<?php
+
+# Generated by the protocol buffer compiler.  DO NOT EDIT!
+# source: google/api/field_behavior.proto
+namespace DeliciousBrains\WP_Offload_Media\Gcp\Google\Api;
+
+use UnexpectedValueException;
+/**
+ * An indicator of the behavior of a given field (for example, that a field
+ * is required in requests, or given as output but ignored as input).
+ * This **does not** change the behavior in protocol buffers itself; it only
+ * denotes the behavior and may affect how API tooling handles the field.
+ * Note: This enum **may** receive new values in the future.
+ *
+ * Protobuf type <code>google.api.FieldBehavior</code>
+ */
+class FieldBehavior
+{
+    /**
+     * Conventional default for enums. Do not use this.
+     *
+     * Generated from protobuf enum <code>FIELD_BEHAVIOR_UNSPECIFIED = 0;</code>
+     */
+    const FIELD_BEHAVIOR_UNSPECIFIED = 0;
+    /**
+     * Specifically denotes a field as optional.
+     * While all fields in protocol buffers are optional, this may be specified
+     * for emphasis if appropriate.
+     *
+     * Generated from protobuf enum <code>OPTIONAL = 1;</code>
+     */
+    const OPTIONAL = 1;
+    /**
+     * Denotes a field as required.
+     * This indicates that the field **must** be provided as part of the request,
+     * and failure to do so will cause an error (usually `INVALID_ARGUMENT`).
+     *
+     * Generated from protobuf enum <code>REQUIRED = 2;</code>
+     */
+    const REQUIRED = 2;
+    /**
+     * Denotes a field as output only.
+     * This indicates that the field is provided in responses, but including the
+     * field in a request does nothing (the server *must* ignore it and
+     * *must not* throw an error as a result of the field's presence).
+     *
+     * Generated from protobuf enum <code>OUTPUT_ONLY = 3;</code>
+     */
+    const OUTPUT_ONLY = 3;
+    /**
+     * Denotes a field as input only.
+     * This indicates that the field is provided in requests, and the
+     * corresponding field is not included in output.
+     *
+     * Generated from protobuf enum <code>INPUT_ONLY = 4;</code>
+     */
+    const INPUT_ONLY = 4;
+    /**
+     * Denotes a field as immutable.
+     * This indicates that the field may be set once in a request to create a
+     * resource, but may not be changed thereafter.
+     *
+     * Generated from protobuf enum <code>IMMUTABLE = 5;</code>
+     */
+    const IMMUTABLE = 5;
+    /**
+     * Denotes that a (repeated) field is an unordered list.
+     * This indicates that the service may provide the elements of the list
+     * in any arbitrary  order, rather than the order the user originally
+     * provided. Additionally, the list's order may or may not be stable.
+     *
+     * Generated from protobuf enum <code>UNORDERED_LIST = 6;</code>
+     */
+    const UNORDERED_LIST = 6;
+    /**
+     * Denotes that this field returns a non-empty default value if not set.
+     * This indicates that if the user provides the empty value in a request,
+     * a non-empty value will be returned. The user will not be aware of what
+     * non-empty value to expect.
+     *
+     * Generated from protobuf enum <code>NON_EMPTY_DEFAULT = 7;</code>
+     */
+    const NON_EMPTY_DEFAULT = 7;
+    /**
+     * Denotes that the field in a resource (a message annotated with
+     * google.api.resource) is used in the resource name to uniquely identify the
+     * resource. For AIP-compliant APIs, this should only be applied to the
+     * `name` field on the resource.
+     * This behavior should not be applied to references to other resources within
+     * the message.
+     * The identifier field of resources often have different field behavior
+     * depending on the request it is embedded in (e.g. for Create methods name
+     * is optional and unused, while for Update methods it is required). Instead
+     * of method-specific annotations, only `IDENTIFIER` is required.
+     *
+     * Generated from protobuf enum <code>IDENTIFIER = 8;</code>
+     */
+    const IDENTIFIER = 8;
+    private static $valueToName = [self::FIELD_BEHAVIOR_UNSPECIFIED => 'FIELD_BEHAVIOR_UNSPECIFIED', self::OPTIONAL => 'OPTIONAL', self::REQUIRED => 'REQUIRED', self::OUTPUT_ONLY => 'OUTPUT_ONLY', self::INPUT_ONLY => 'INPUT_ONLY', self::IMMUTABLE => 'IMMUTABLE', self::UNORDERED_LIST => 'UNORDERED_LIST', self::NON_EMPTY_DEFAULT => 'NON_EMPTY_DEFAULT', self::IDENTIFIER => 'IDENTIFIER'];
+    public static function name($value)
+    {
+        if (!isset(self::$valueToName[$value])) {
+            throw new UnexpectedValueException(\sprintf('Enum %s has no name defined for value %s', __CLASS__, $value));
+        }
+        return self::$valueToName[$value];
+    }
+    public static function value($name)
+    {
+        $const = __CLASS__ . '::' . \strtoupper($name);
+        if (!\defined($const)) {
+            throw new UnexpectedValueException(\sprintf('Enum %s has no value defined for name %s', __CLASS__, $name));
+        }
+        return \constant($const);
+    }
+}