feat: Add PostgreSQL and Redis client support

- Add PostgreSQL client functionality for database interactions.
- Add Redis client functionality for cache and data store operations.
- Extend Rhai scripting with PostgreSQL and Redis client modules.
- Add documentation and test cases for both clients.

docs/rhai/postgresclient_module_tests.md

@@ -0,0 +1,114 @@
+# PostgreSQL Client Module Tests
+
+The PostgreSQL client module provides functions for connecting to and interacting with PostgreSQL databases. These tests verify the functionality of the module.
+
+## PostgreSQL Client Features
+
+The PostgreSQL client module provides the following features:
+
+1. **Basic PostgreSQL Operations**: Execute queries, fetch results, etc.
+2. **Connection Management**: Automatic connection handling and reconnection
+3. **Builder Pattern for Configuration**: Flexible configuration with authentication support
+
+## Prerequisites
+
+- PostgreSQL server must be running and accessible
+- Environment variables should be set for connection details:
+  - `POSTGRES_HOST`: PostgreSQL server host (default: localhost)
+  - `POSTGRES_PORT`: PostgreSQL server port (default: 5432)
+  - `POSTGRES_USER`: PostgreSQL username (default: postgres)
+  - `POSTGRES_PASSWORD`: PostgreSQL password
+  - `POSTGRES_DB`: PostgreSQL database name (default: postgres)
+
+## Test Files
+
+### 01_postgres_connection.rhai
+
+Tests basic PostgreSQL connection and operations:
+
+- Connecting to PostgreSQL
+- Pinging the server
+- Creating a table
+- Inserting data
+- Querying data
+- Dropping a table
+- Resetting the connection
+
+### run_all_tests.rhai
+
+Runs all PostgreSQL client module tests and provides a summary of the results.
+
+## Running the Tests
+
+You can run the tests using the `herodo` command:
+
+```bash
+herodo --path src/rhai_tests/postgresclient/run_all_tests.rhai
+```
+
+Or run individual tests:
+
+```bash
+herodo --path src/rhai_tests/postgresclient/01_postgres_connection.rhai
+```
+
+## Available Functions
+
+### Connection Functions
+
+- `pg_connect()`: Connect to PostgreSQL using environment variables
+- `pg_ping()`: Ping the PostgreSQL server to check if it's available
+- `pg_reset()`: Reset the PostgreSQL client connection
+
+### Query Functions
+
+- `pg_execute(query)`: Execute a query and return the number of affected rows
+- `pg_query(query)`: Execute a query and return the results as an array of maps
+- `pg_query_one(query)`: Execute a query and return a single row as a map
+
+## Authentication Support
+
+The PostgreSQL client module will support authentication using the builder pattern in a future update.
+
+The backend implementation is ready, but the Rhai bindings are still in development.
+
+When implemented, the builder pattern will support the following configuration options:
+
+- Host: Set the PostgreSQL host
+- Port: Set the PostgreSQL port
+- User: Set the PostgreSQL username
+- Password: Set the PostgreSQL password
+- Database: Set the PostgreSQL database name
+- Application name: Set the application name
+- Connection timeout: Set the connection timeout in seconds
+- SSL mode: Set the SSL mode
+
+## Example Usage
+
+```javascript
+// Connect to PostgreSQL
+if (pg_connect()) {
+    print("Connected to PostgreSQL!");
+
+    // Create a table
+    let create_table_query = "CREATE TABLE IF NOT EXISTS test_table (id SERIAL PRIMARY KEY, name TEXT)";
+    pg_execute(create_table_query);
+
+    // Insert data
+    let insert_query = "INSERT INTO test_table (name) VALUES ('test')";
+    pg_execute(insert_query);
+
+    // Query data
+    let select_query = "SELECT * FROM test_table";
+    let results = pg_query(select_query);
+
+    // Process results
+    for (result in results) {
+        print(`ID: ${result.id}, Name: ${result.name}`);
+    }
+
+    // Clean up
+    let drop_query = "DROP TABLE test_table";
+    pg_execute(drop_query);
+}
+```