Updates README

Author: BilalBudhani

README.md

@@ -4,9 +4,34 @@
 
 Fileboost is a Rails gem that provides seamless integration with the Fileboost.dev image optimization service. It offers drop-in replacement helpers for Rails' native image helpers with automatic optimization, HMAC authentication, and comprehensive transformation support for ActiveStorage objects.
 
+## Table of Contents
+
+- [Features](#features)
+- [Installation](#installation)
+- [Configuration](#configuration)
+- [Usage](#usage)
+  - [Drop-in Replacement (Recommended)](#drop-in-replacement-recommended)
+  - [Manual Helper Method](#manual-helper-method)
+  - [URL Generation](#url-generation)
+  - [Transformation Options](#transformation-options)
+  - [Parameter Aliases](#parameter-aliases)
+  - [ActiveStorage Support](#activestorage-support)
+  - [ActiveStorage Variants (NEW in v0.2.0)](#activestorage-variants-new-in-v020)
+    - [Variant Transformation Mapping](#variant-transformation-mapping)
+    - [Combining Variants with Custom Options](#combining-variants-with-custom-options)
+  - [Responsive Images](#responsive-images)
+- [Error Handling](#error-handling)
+- [Security](#security)
+- [Development](#development)
+- [Testing](#testing)
+- [Contributing](#contributing)
+- [License](#license)
+- [Support](#support)
+
 ## Features
 
 - 🚀 **Drop-in replacement** for Rails `image_tag` with zero code changes (NEW in v0.2.0)
+- 🎨 **Full ActiveStorage Variant support** with automatic transformation mapping (NEW in v0.2.0)
 - 🔒 **Secure HMAC authentication** with Fileboost.dev service
 - 📱 **ActiveStorage only** - works exclusively with ActiveStorage attachments
 - 🎛️ **Comprehensive transformations** - resize, quality, format conversion, and more
@@ -79,13 +104,18 @@ With this enabled, your existing Rails code automatically gets Fileboost optimiz
 <%= image_tag user.avatar, resize: { w: 300, h: 300 }, alt: "Avatar" %>
 <%= image_tag post.featured_image, resize: { width: 800, quality: 85 }, class: "hero" %>
 
+<!-- ActiveStorage variants work seamlessly -->
+<%= image_tag user.avatar.variant(resize_to_limit: [100, 100]), alt: "Thumbnail" %>
+<%= image_tag post.image.variant(:thumb), alt: "Post thumbnail" %>
+
 <!-- Non-ActiveStorage images work exactly as before -->
 <%= image_tag "/assets/logo.png", alt: "Logo" %>
 <%= image_tag "https://example.com/image.jpg", alt: "External" %>
 ```
 
 **Benefits:**
 - Zero code changes required for existing ActiveStorage images
+- Full ActiveStorage variant support with automatic transformation mapping
 - Automatic fallback to Rails behavior for non-ActiveStorage assets
 - Gradual migration path - enable/disable with single configuration option
 
@@ -167,6 +197,64 @@ Works seamlessly with all ActiveStorage attachment types:
 <%= fileboost_image_tag post.featured_image.blob, resize: { w: 800 } %>
 ```
 
+### ActiveStorage Variants (NEW in v0.2.0)
+
+Fileboost now provides full support for ActiveStorage variants with automatic transformation mapping:
+
+```erb
+<!-- Basic variants with automatic transformation mapping -->
+<%= image_tag user.avatar.variant(resize_to_limit: [200, 200]) %>
+<!-- ↓ Automatically becomes: w=200&h=200&fit=scale-down -->
+
+<%= image_tag post.image.variant(resize_to_fit: [400, 300]) %>
+<!-- ↓ Automatically becomes: w=400&h=300&fit=contain -->
+
+<%= image_tag hero.banner.variant(resize_to_fill: [800, 400]) %>
+<!-- ↓ Automatically becomes: w=800&h=400&fit=cover -->
+
+<!-- Complex variants with multiple transformations -->
+<%= image_tag post.image.variant(
+  resize_to_limit: [600, 400],
+  quality: 85,
+  format: :webp
+) %>
+<!-- ↓ Automatically becomes: w=600&h=400&fit=scale-down&q=85&f=webp -->
+
+<!-- Named variants work seamlessly -->
+<%= image_tag user.avatar.variant(:thumb) %>
+<!-- ↓ Uses predefined variant transformations -->
+```
+
+#### Variant Transformation Mapping
+
+Fileboost automatically maps ActiveStorage variant transformations to optimized URL parameters:
+
+| ActiveStorage Variant | Fileboost Parameters | Description |
+|----------------------|---------------------|-------------|
+| `resize_to_limit: [w, h]` | `w=W&h=H&fit=scale-down` | Resize within bounds, preserving aspect ratio |
+| `resize_to_fit: [w, h]` | `w=W&h=H&fit=contain` | Resize to fit exactly, with letterboxing if needed |
+| `resize_to_fill: [w, h]` | `w=W&h=H&fit=cover` | Resize and crop to fill exactly |
+| `resize_and_pad: [w, h]` | `w=W&h=H&fit=pad` | Resize with padding |
+| `quality: 85` | `q=85` | JPEG/WebP quality (1-100) |
+| `format: :webp` | `f=webp` | Output format |
+| `rotate: "-90"` | `r=-90` | Rotation in degrees |
+
+#### Combining Variants with Custom Options
+
+You can combine variant transformations with additional Fileboost options:
+
+```erb
+<!-- Variant transformations + additional options -->
+<%= image_tag user.avatar.variant(resize_to_limit: [200, 200]), 
+    resize: { blur: 5, brightness: 110 } %>
+<!-- ↓ Combines variant params with additional blur and brightness -->
+
+<!-- Override variant parameters -->
+<%= image_tag post.image.variant(resize_to_limit: [400, 300]),
+    resize: { w: 500 } %>  
+<!-- ↓ Uses h=300&fit=scale-down from variant, but overrides width to 500 -->
+```
+
 ### Responsive Images
 
 Generate multiple sizes for responsive designs: