🔒 Add environment-based configuration system

- Add .env.example template with all configurable values
- Create comprehensive .gitignore for personal data
- Add sanitization script to remove hardcoded personal info
- Add environment-aware deployment scripts
- Add ENVIRONMENT.md documentation
- Keep personal information in .env (gitignored)

This makes the repository safe for public sharing while keeping personal domains, emails, and secrets secure.

scripts/prepare-deployment.sh

@@ -0,0 +1,77 @@
+#!/bin/bash
+set -e
+
+# Environment-aware deployment script
+echo "🚀 Environment-aware deployment script..."
+
+# Load environment variables
+if [ -f ".env" ]; then
+  echo "📋 Loading configuration from .env file..."
+  export $(grep -v '^#' .env | xargs)
+else
+  echo "❌ No .env file found! Please create one from .env.example"
+  exit 1
+fi
+
+# Validate required environment variables
+required_vars=(
+  "BASE_DOMAIN"
+  "WEBHOOK_DOMAIN" 
+  "KNATIVE_DOMAIN"
+  "GITHUB_REPOSITORY"
+  "CONTAINER_REGISTRY"
+)
+
+for var in "${required_vars[@]}"; do
+  if [ -z "${!var}" ]; then
+    echo "❌ Required environment variable $var is not set!"
+    exit 1
+  fi
+done
+
+echo "✅ Environment validation passed"
+echo "   Base Domain: $BASE_DOMAIN"
+echo "   Webhook Domain: $WEBHOOK_DOMAIN"
+echo "   GitHub Repository: $GITHUB_REPOSITORY"
+
+# Function to substitute environment variables in manifests
+substitute_env_vars() {
+  local source_dir="$1"
+  local target_dir="$2"
+  
+  echo "📝 Substituting environment variables: $source_dir -> $target_dir"
+  
+  # Create target directory
+  mkdir -p "$target_dir"
+  
+  # Process all YAML files
+  for file in "$source_dir"/*.yml "$source_dir"/*.yaml; do
+    if [ -f "$file" ]; then
+      local basename=$(basename "$file")
+      local target_file="$target_dir/$basename"
+      
+      # Substitute environment variables
+      envsubst < "$file" > "$target_file"
+      echo "   ✅ $basename"
+    fi
+  done
+}
+
+# Create deployment-ready manifests from templates
+if [ -d "manifests/templates" ]; then
+  echo "🔄 Creating deployment manifests from templates..."
+  
+  substitute_env_vars "manifests/templates/dev" "manifests/dev"
+  substitute_env_vars "manifests/templates/staging" "manifests/staging"  
+  substitute_env_vars "manifests/templates/prod" "manifests/prod"
+  substitute_env_vars "manifests/templates" "manifests"
+  
+  echo "✅ Deployment manifests ready"
+else
+  echo "⚠️ No templates directory found, using existing manifests"
+fi
+
+echo ""
+echo "🎯 Ready for deployment with your environment configuration!"
+echo "   Run: kubectl apply -f manifests/dev/"
+echo "   Or use: ./scripts/setup-webhook-deployment.sh"