[2.9.0] Rename plugin to compound-engineering

BREAKING: Plugin renamed from compounding-engineering to compound-engineering.
Users will need to reinstall with the new name:

  claude /plugin install compound-engineering

Changes:
- Renamed plugin directory and all references
- Updated documentation counts (24 agents, 19 commands)
- Added julik-frontend-races-reviewer to docs

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

plugins/compound-engineering/skills/andrew-kane-gem-writer/SKILL.md

@@ -0,0 +1,184 @@
+---
+name: andrew-kane-gem-writer
+description: Write Ruby gems following Andrew Kane's proven patterns and philosophy. Use when creating new Ruby gems, refactoring existing gems, designing gem APIs, or when the user wants clean, minimal, production-ready Ruby library code. Triggers on requests like "create a gem", "write a Ruby library", "design a gem API", or mentions of Andrew Kane's style.
+---
+
+# Andrew Kane Gem Writer
+
+Write Ruby gems following Andrew Kane's battle-tested patterns from 100+ gems with 374M+ downloads (Searchkick, PgHero, Chartkick, Strong Migrations, Lockbox, Ahoy, Blazer, Groupdate, Neighbor, Blind Index).
+
+## Core Philosophy
+
+**Simplicity over cleverness.** Zero or minimal dependencies. Explicit code over metaprogramming. Rails integration without Rails coupling. Every pattern serves production use cases.
+
+## Entry Point Structure
+
+Every gem follows this exact pattern in `lib/gemname.rb`:
+
+```ruby
+# 1. Dependencies (stdlib preferred)
+require "forwardable"
+
+# 2. Internal modules
+require_relative "gemname/model"
+require_relative "gemname/version"
+
+# 3. Conditional Rails (CRITICAL - never require Rails directly)
+require_relative "gemname/railtie" if defined?(Rails)
+
+# 4. Module with config and errors
+module GemName
+  class Error < StandardError; end
+  class InvalidConfigError < Error; end
+
+  class << self
+    attr_accessor :timeout, :logger
+    attr_writer :client
+  end
+
+  self.timeout = 10  # Defaults set immediately
+end
+```
+
+## Class Macro DSL Pattern
+
+The signature Kane pattern—single method call configures everything:
+
+```ruby
+# Usage
+class Product < ApplicationRecord
+  searchkick word_start: [:name]
+end
+
+# Implementation
+module GemName
+  module Model
+    def gemname(**options)
+      unknown = options.keys - KNOWN_KEYWORDS
+      raise ArgumentError, "unknown keywords: #{unknown.join(", ")}" if unknown.any?
+
+      mod = Module.new
+      mod.module_eval do
+        define_method :some_method do
+          # implementation
+        end unless method_defined?(:some_method)
+      end
+      include mod
+
+      class_eval do
+        cattr_reader :gemname_options, instance_reader: false
+        class_variable_set :@@gemname_options, options.dup
+      end
+    end
+  end
+end
+```
+
+## Rails Integration
+
+**Always use `ActiveSupport.on_load`—never require Rails gems directly:**
+
+```ruby
+# WRONG
+require "active_record"
+ActiveRecord::Base.include(MyGem::Model)
+
+# CORRECT
+ActiveSupport.on_load(:active_record) do
+  extend GemName::Model
+end
+
+# Use prepend for behavior modification
+ActiveSupport.on_load(:active_record) do
+  ActiveRecord::Migration.prepend(GemName::Migration)
+end
+```
+
+## Configuration Pattern
+
+Use `class << self` with `attr_accessor`, not Configuration objects:
+
+```ruby
+module GemName
+  class << self
+    attr_accessor :timeout, :logger
+    attr_writer :master_key
+  end
+
+  def self.master_key
+    @master_key ||= ENV["GEMNAME_MASTER_KEY"]
+  end
+
+  self.timeout = 10
+  self.logger = nil
+end
+```
+
+## Error Handling
+
+Simple hierarchy with informative messages:
+
+```ruby
+module GemName
+  class Error < StandardError; end
+  class ConfigError < Error; end
+  class ValidationError < Error; end
+end
+
+# Validate early with ArgumentError
+def initialize(key:)
+  raise ArgumentError, "Key must be 32 bytes" unless key&.bytesize == 32
+end
+```
+
+## Testing (Minitest Only)
+
+```ruby
+# test/test_helper.rb
+require "bundler/setup"
+Bundler.require(:default)
+require "minitest/autorun"
+require "minitest/pride"
+
+# test/model_test.rb
+class ModelTest < Minitest::Test
+  def test_basic_functionality
+    assert_equal expected, actual
+  end
+end
+```
+
+## Gemspec Pattern
+
+Zero runtime dependencies when possible:
+
+```ruby
+Gem::Specification.new do |spec|
+  spec.name = "gemname"
+  spec.version = GemName::VERSION
+  spec.required_ruby_version = ">= 3.1"
+  spec.files = Dir["*.{md,txt}", "{lib}/**/*"]
+  spec.require_path = "lib"
+  # NO add_dependency lines - dev deps go in Gemfile
+end
+```
+
+## Anti-Patterns to Avoid
+
+- `method_missing` (use `define_method` instead)
+- Configuration objects (use class accessors)
+- `@@class_variables` (use `class << self`)
+- Requiring Rails gems directly
+- Many runtime dependencies
+- Committing Gemfile.lock in gems
+- RSpec (use Minitest)
+- Heavy DSLs (prefer explicit Ruby)
+
+## Reference Files
+
+For deeper patterns, see:
+- **[references/module-organization.md](references/module-organization.md)** - Directory layouts, method decomposition
+- **[references/rails-integration.md](references/rails-integration.md)** - Railtie, Engine, on_load patterns
+- **[references/database-adapters.md](references/database-adapters.md)** - Multi-database support patterns
+- **[references/testing-patterns.md](references/testing-patterns.md)** - Multi-version testing, CI setup
+- **[references/resources.md](references/resources.md)** - Links to Kane's repos and articles