feat(logging): add database logging support and refactor logging system

- Implement new database logging functionality with separate logs database
- Refactor PostLog function to store logs in database while maintaining console output
- Add new InitLogsDatabase function and related database operations
- Update main.go to support separate database paths for data and logs
- Add logging for user creation events

postLog/database.go

@@ -0,0 +1,60 @@
+package postLog
+
+import (
+	"database/sql"
+	"fmt"
+	"os"
+	"time"
+)
+
+var (
+	logsDB    *sql.DB
+	tableName string
+)
+
+func InitLogsDatabase(dbPath string) error {
+	var err error
+	logsDB, err = sql.Open("sqlite", dbPath)
+	if err != nil {
+		return fmt.Errorf("failed to open logs database: %w", err)
+	}
+
+	if err = logsDB.Ping(); err != nil {
+		return fmt.Errorf("failed to ping logs database: %w", err)
+	}
+
+	timestamp := time.Now().Format("20060102_150405")
+	tableName = fmt.Sprintf("logs_%s", timestamp)
+
+	createTableSQL := fmt.Sprintf(`
+	CREATE TABLE IF NOT EXISTS %s (
+		id INTEGER PRIMARY KEY AUTOINCREMENT,
+		level INTEGER NOT NULL,
+		content TEXT NOT NULL,
+		timestamp TEXT NOT NULL DEFAULT (datetime('now'))
+	);`, tableName)
+
+	_, err = logsDB.Exec(createTableSQL)
+	if err != nil {
+		return fmt.Errorf("failed to create logs table %s: %w", tableName, err)
+	}
+
+	return nil
+}
+
+func insertLogToDB(db *sql.DB, level int, content string, timestamp string) {
+	if db != nil {
+		_, err := db.Exec(fmt.Sprintf(`INSERT INTO %s (level, content, timestamp) VALUES (%d, '%s', '%s')`, tableName,
+			level, content, timestamp))
+		// fmt.Fprintf(os.Stderr, `INSERT INTO %s (level, content, timestamp) VALUES (%d, '%s', '%s')`, tableName, level, content, timestamp)
+		if err != nil {
+			fmt.Fprintf(os.Stderr, "Failed to write log to database: %v\n", err)
+		}
+	}
+}
+
+func SetLogsDatabase(db *sql.DB) {
+	loggerMutex.Lock()
+	defer loggerMutex.Unlock()
+	logsDB = db
+}