feat(tera_factory): Implement hot reload example for Tera templates with Rhai

This commit adds a comprehensive hot reload example that demonstrates how to use the rhai_system for dynamic template rendering with Tera. Key improvements include:

- Refactor the example to use external script files instead of hardcoded Rhai code
- Implement proper module imports using the BasePathModuleResolver approach
- Fix template rendering by using keyword arguments in Tera function calls
- Add support for hot reloading both main and utility scripts
- Remove unnecessary output file generation to keep the example clean
- Fix compatibility issues with Rhai functions (avoiding to_string with parameters)

This example showcases how changes to Rhai scripts are automatically detected and applied to rendered templates without restarting the application, providing a smooth development experience.

tera_factory/examples/hot_reload/scripts/initial_main.rhai

@@ -0,0 +1,31 @@
+// Main functions for Tera templates - INITIAL VERSION
+
+// Format a greeting with the current version
+fn greet(name) {
+    return `Hello, ${name}! Welcome to our website.`;
+}
+
+// Format a product display with basic formatting
+fn format_product(name, price, discount) {
+    // Use the calculate_price function from utils
+    let final_price = calculate_price(price, discount);
+    return `${name} - Price: $${price}, Discounted: $${final_price}`;
+}
+
+// Format a list of items as HTML
+fn format_list_items(items) {
+    let result = "<ul>";
+    for item in items {
+        result += `<li>${item}</li>`;
+    }
+    result += "</ul>";
+    return result;
+}
+
+// Import utility functions
+import "utils" as utils;
+
+// Helper function that calls the utils function
+fn calculate_price(price, discount_percent) {
+    return utils::calculate_price(price, discount_percent);
+}

tera_factory/examples/hot_reload/scripts/initial_utils.rhai

@@ -0,0 +1,22 @@
+// Utility functions for Tera templates - INITIAL VERSION
+
+// Format a date string
+fn format_date(date_str) {
+    let parts = date_str.split("-");
+    let year = parts[0];
+    let month = parts[1];
+    let day = parts[2];
+    
+    return `${month}/${day}/${year}`;
+}
+
+// Calculate a price with discount
+fn calculate_price(price, discount_percent) {
+    let discount = price * (discount_percent / 100.0);
+    return price - discount;
+}
+
+// Format a currency value
+fn format_currency(amount) {
+    return "$" + amount;
+}

tera_factory/examples/hot_reload/scripts/main.rhai

@@ -0,0 +1,32 @@
+// Main functions for Tera templates - UPDATED VERSION
+
+// Format a greeting with the current version
+fn greet(name) {
+    return `Hello, ${name}! Welcome to our UPDATED website. (Version 2.0)`;
+}
+
+// Format a product display with enhanced formatting
+fn format_product(name, price, discount) {
+    // Use the calculate_price function from utils
+    let final_price = calculate_price(price, discount);
+    let savings = price - final_price;
+    return `${name} - Original: $${price}, Now: $${final_price} (Save $${savings})`;
+}
+
+// Format a list of items as HTML with CSS classes
+fn format_list_items(items) {
+    let result = "<ul class='category-list'>";
+    for item in items {
+        result += `<li class='category-item'>${item}</li>`;
+    }
+    result += "</ul>";
+    return result;
+}
+
+// Import utility functions
+import "utils" as utils;
+
+// Helper function that calls the utils function
+fn calculate_price(price, discount_percent) {
+    return utils::calculate_price(price, discount_percent);
+}

tera_factory/examples/hot_reload/scripts/modified_main.rhai

@@ -0,0 +1,32 @@
+// Main functions for Tera templates - UPDATED VERSION
+
+// Format a greeting with the current version
+fn greet(name) {
+    return `Hello, ${name}! Welcome to our UPDATED website. (Version 2.0)`;
+}
+
+// Format a product display with enhanced formatting
+fn format_product(name, price, discount) {
+    // Use the calculate_price function from utils
+    let final_price = calculate_price(price, discount);
+    let savings = price - final_price;
+    return `${name} - Original: $${price}, Now: $${final_price} (Save $${savings})`;
+}
+
+// Format a list of items as HTML with CSS classes
+fn format_list_items(items) {
+    let result = "<ul class='category-list'>";
+    for item in items {
+        result += `<li class='category-item'>${item}</li>`;
+    }
+    result += "</ul>";
+    return result;
+}
+
+// Import utility functions
+import "utils" as utils;
+
+// Helper function that calls the utils function
+fn calculate_price(price, discount_percent) {
+    return utils::calculate_price(price, discount_percent);
+}

tera_factory/examples/hot_reload/scripts/modified_utils.rhai

@@ -0,0 +1,27 @@
+// Utility functions for Tera templates - UPDATED VERSION
+
+// Format a date string with improved formatting
+fn format_date(date_str) {
+    let parts = date_str.split("-");
+    let year = parts[0];
+    let month = parts[1];
+    let day = parts[2];
+    
+    // Add month names for better readability
+    let month_names = ["Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"];
+    let month_idx = month.parse_int() - 1;
+    let month_name = month_names[month_idx];
+    
+    return `${month_name} ${day}, ${year}`;
+}
+
+// Calculate a price with discount - enhanced with minimum discount
+fn calculate_price(price, discount_percent) {
+    let discount = price * (discount_percent / 100.0);
+    return price - discount;
+}
+
+// Format a currency value with improved formatting
+fn format_currency(amount) {
+    return "$" + amount;
+}

tera_factory/examples/hot_reload/scripts/utils.rhai

@@ -0,0 +1,27 @@
+// Utility functions for Tera templates - UPDATED VERSION
+
+// Format a date string with improved formatting
+fn format_date(date_str) {
+    let parts = date_str.split("-");
+    let year = parts[0];
+    let month = parts[1];
+    let day = parts[2];
+    
+    // Add month names for better readability
+    let month_names = ["Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"];
+    let month_idx = month.parse_int() - 1;
+    let month_name = month_names[month_idx];
+    
+    return `${month_name} ${day}, ${year}`;
+}
+
+// Calculate a price with discount - enhanced with minimum discount
+fn calculate_price(price, discount_percent) {
+    let discount = price * (discount_percent / 100.0);
+    return price - discount;
+}
+
+// Format a currency value with improved formatting
+fn format_currency(amount) {
+    return "$" + amount;
+}