fix(launch): Added parameter

doc/architecture/managers/DatabaseManager.md

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+# DatabaseManager (`assignments::one::DatabaseManager`)
+
+## Overview
+
+The `DatabaseManager` class is a PostgreSQL database interface for the ROS2 grade calculator.
+It handles all database operations including connection management, table creation and data insertion.
+
+## Implementation Details
+
+### Dependencies
+- **pqxx**: Modern C++ PostgreSQL library for database connectivity
+- **rclcpp**: ROS2 C++ client library for logging
+- **ConfigManager**: Configuration manager for database settings
+
+### Key Components
+
+#### Constructor
+```cpp
+DatabaseManager(rclcpp::Logger logger)
+```
+- Initializes the database manager with ROS2 logging
+- Creates a ConfigManager instance for configuration handling
+- Automatically calls `init_database()` to establish connection and setup
+
+#### Connection Management
+
+**`bool connect(const std::string& connection_string)`**
+> Returns `true` on successful connection, `false` on failure
+
+- Establishes connection to PostgreSQL database using connection information from the config TOML
+- Connection string format: `"host=localhost port=5432 dbname=grades user=postgres password=postgres"`
+
+**`bool is_connected() const`**
+>  Returns `true` if connection exists and is open
+
+- Check for active database connection status
+
+#### Database Initialization
+
+**`void init_database()`**
+- Database setup process
+- Loads configuration from ConfigManager
+- Establishes connection using configuration settings
+- Creates necessary tables and inserts sample data
+- Error handling for configuration and connection failures
+
+**`void create_tables()`**
+- Creates all required database tables using SQL queries from `SQLQueries.hpp`
+- Tables created:
+  - `enrollments`: Student course enrollments
+  - `exam_results`: Individual exam scores
+  - `course_results`: Final course grades and statistics
+- Uses transactions for atomic table creation
+
+**`void insert_sample_data()`**
+- Inserts predefined sample student data
+
+### Data Operations
+
+#### Student Course Management
+
+**`std::vector<StudentCourse> queue_pending_combinations()`**
+> Returns vector of StudentCourse objects for processing queue
+
+- Gets all student-course combinations that need exam results generated
+- Executes complex SQL query to find missing exam results
+
+**`bool enroll_student_into_course(const StudentCourse& sc)`**
+> Returns `true` on successful enrollment, `false` on failure
+
+- Enrolls a student into a specific course
+
+#### Exam Result Processing
+
+**`bool store_exam_result(const std::string& student_name, const std::string& course_name, int grade)`**
+- Stores individual exam results in the database
+- Parameters:
+  - `student_name`: Name of the student
+  - `course_name`: Name of the course
+  - `grade`: Exam score (10-100)
+
+**`bool store_final_course_result(const StudentCourse& sc, int exam_count, int final_grade)`**
+- Stores calculated final course results
+- Parameters:
+  - `sc`: StudentCourse object containing student and course names
+  - `exam_count`: Number of exams taken
+  - `final_grade`: Calculated final grade
+- Used by grade calculation nodes for final result storage
+
+#### Grade Retrieval
+
+**`int get_final_course_grade(const StudentCourse& sc)`**
+> Returns:
+>  - `> 0`: Valid final grade (rounded average)
+>  - `-1`: No exams taken or no results found
+
+- Gets final calculated grade for a student-course combination
+- Performs average calculation with proper rounding
+- Used by nodes to check if final grading is complete
+
+### Logging
+
+- Uses ROS2 logger with `[DBS]` prefix for database operations
+- Different log levels:
+  - `INFO`: Successful operations, connection status
+  - `ERROR`: SQL errors, connection failures, configuration issues
+  - `WARN`: Non-critical issues, missing configurations
+
+
+### Usage Examples
+
+#### Basic Database Setup
+```cpp
+// Create DatabaseManager with ROS2 logger
+DatabaseManager db_manager(node->get_logger());
+
+// Check connection status
+if (db_manager.is_connected()) {
+    // Database ready for operations
+    bool success = db_manager.store_exam_result("Wessel", "ROS2", 85);
+    if (success) {
+        RCLCPP_INFO(logger, "Exam result stored successfully");
+    }
+}
+```