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/basic/Cargo.toml

@@ -0,0 +1,11 @@
+[package]
+name = "tera-factory-example"
+version = "0.1.0"
+edition = "2021"
+
+[dependencies]
+tera_factory = { path = "../.." }
+rhai_factory = { path = "../../../rhai_factory" }
+tera = "1.19.0"
+rhai = { version = "1.15.1", features = ["sync"] }
+env_logger = "0.11"