Fix markdownlint issues: wrap long lines and add language specifiers

Author: justin808

AI_AGENT_INSTRUCTIONS.md

@@ -1,6 +1,7 @@
 # 🤖 AI Agent Instructions: React on Rails Setup
 
-_Super concise, copy-paste instructions for AI agents to set up React on Rails in common scenarios._
+_Super concise, copy-paste instructions for AI agents to set up React on Rails in
+common scenarios._
 
 ## 🔍 **Before Starting: Check Current Versions**
 
@@ -15,7 +16,8 @@ gem search shakapacker --remote
 # shakapacker ~> 8.3
 ```
 
-**⚠️ Version Flexibility:** These instructions use `~> X.Y` which allows patch updates. Always check for latest versions before starting a new project.
+**⚠️ Version Flexibility:** These instructions use `~> X.Y` which allows patch
+updates. Always check for latest versions before starting a new project.
 
 ## 🚨 **CRITICAL: Installation Order Matters**
 
@@ -28,13 +30,13 @@ gem search shakapacker --remote
 
 **✅ Correct Order:**
 
-```
+```text
 Shakapacker → package.json created → React on Rails → success
 ```
 
 **❌ Wrong Order:**
 
-```
+```text
 React on Rails → no package.json → ERROR: package.json not found
 ```
 
@@ -61,7 +63,8 @@ rails generate react_on_rails:install
 bin/dev
 ```
 
-**✅ Success Check:** Visit `http://localhost:3000/hello_world` → Should see "Hello World" from React
+**✅ Success Check:** Visit `http://localhost:3000/hello_world` → Should see
+"Hello World" from React
 
 **📁 Generated Files:**
 
@@ -214,7 +217,7 @@ bin/dev
 
 ### Essential Files Structure
 
-```
+```text
 app/
 ├── controllers/hello_world_controller.rb
 ├── views/hello_world/index.html.erb
@@ -231,7 +234,8 @@ app/
 
 ### Version Requirements
 
-- Rails 7+ (Rails 8 supported), Ruby 3.0+ (Ruby 3.2+ for Rails 8), Node 20+ LTS, Yarn
+- Rails 7+ (Rails 8 supported), Ruby 3.0+ (Ruby 3.2+ for Rails 8), Node 20+
+  LTS, Yarn
 - react_on_rails ~> 15.0+, shakapacker ~> 8.3+
 - **Note**: Use `bundle info react_on_rails` to check latest available version