Improve logging, shutdown behavior, and build configuration:

- Enabled `immediateFlush` for log appenders and disabled `shutdownHook` in Log4j2 configuration.
- Enhanced shutdown hook with graceful Log4j2 termination and extended delay for log flushing.
- Improved database connection closure logging in `DatabaseManager`.
- Integrated Maven Shade Plugin to create executable JARs with all dependencies.

src/main/java/com/mediamanager/MediaManagerApplication.java

@@ -32,19 +32,28 @@ public class MediaManagerApplication {
 
             // Keep application running
             Runtime.getRuntime().addShutdownHook(new Thread(() -> {
+
                 logger.info("Shutting down MediaManager Core...");
+
+
                 if (databaseManager != null) {
                     databaseManager.close();
                 }
 
-                // TODO: Cleanup resources
 
                 logger.info("MediaManager Core shutdown successfully");
+                logger.info("Goodbye!");
+
+
+                // Give Log4j2 time to write all pending messages before shutting down
                 try {
-                    Thread.sleep(500);
+                    Thread.sleep(1000);
                 } catch (InterruptedException e) {
                     Thread.currentThread().interrupt();
                 }
+
+                // Now shutdown Log4j2
+                org.apache.logging.log4j.LogManager.shutdown();
             }));
             logger.info("Application is running");
             logger.info("Press Ctrl+C to exit");

src/main/java/com/mediamanager/service/database/DatabaseManager.java

@@ -88,11 +88,14 @@ public class DatabaseManager {
     public void close() {
         if (connection != null) {
             try {
+                logger.info("Closing database connection...");
                 connection.close();
                 logger.info("Database connection closed successfully");
             } catch (SQLException e) {
-                logger.error("Failed to close database connection", e);
+                logger.error("Error closing database connection: {}", e.getMessage());
             }
+        } else {
+            logger.debug("No database connection to close");
         }
     }
 }