feat: migrate to DragonflyDB and clean up environment configuration

- Replace Redis with DragonflyDB for better performance and memory efficiency
- Remove redundant environment variables (POSTGRES_*, ENCRYPTION_KEY, OAUTH_SERVICE_URL)
- Consolidate database configuration to use single DB_* variables
- Use JWT_SECRET for both JWT tokens and encryption
- Remove PORT variable redundancy, use BACKEND_PORT consistently
- Clean up docker-compose configurations for dev/prod consistency
- Add DragonflyDB configuration with optimized memory usage
- Remove redis.conf as it's no longer needed
- Update health checks to use Redis-compatible CLI for DragonflyDB
- Add missing VITE_API_URL to production frontend
- Fix GitHub Actions to use correct go.sum path
- Clean up development directories and unused files

backend/examples/user_service_example.go

@@ -0,0 +1,156 @@
+package examples
+
+import (
+	"context"
+	"fmt"
+
+	"github.com/jackc/pgx/v5/pgtype"
+	"github.com/trackeep/backend/internal/db"
+	"github.com/trackeep/backend/internal/db/sqlc"
+)
+
+// UserServiceExample demonstrates how to use sqlc with typed queries
+type UserServiceExample struct {
+	db *db.DB
+}
+
+// NewUserServiceExample creates a new user service example
+func NewUserServiceExample(database *db.DB) *UserServiceExample {
+	return &UserServiceExample{
+		db: database,
+	}
+}
+
+// CreateUserExample shows how to create a user with typed queries
+func (s *UserServiceExample) CreateUserExample(ctx context.Context, email, passwordHash, firstName, lastName string) (sqlc.User, error) {
+	// Use typed query - no SQL strings, no reflection
+	user, err := s.db.CreateUser(ctx, sqlc.CreateUserParams{
+		Email:        email,
+		PasswordHash: passwordHash,
+		FirstName:    &firstName,
+		LastName:     &lastName,
+		IsActive:     &[]bool{true}[0],
+		IsVerified:   &[]bool{false}[0],
+	})
+	if err != nil {
+		return sqlc.User{}, fmt.Errorf("failed to create user: %w", err)
+	}
+
+	// Convert CreateUserRow to User
+	return sqlc.User{
+		ID:         user.ID,
+		Email:      user.Email,
+		FirstName:  user.FirstName,
+		LastName:   user.LastName,
+		AvatarUrl:  user.AvatarUrl,
+		IsActive:   user.IsActive,
+		IsVerified: user.IsVerified,
+		LastLogin:  user.LastLogin,
+		CreatedAt:  user.CreatedAt,
+		UpdatedAt:  user.UpdatedAt,
+	}, nil
+}
+
+// GetUserExample shows how to get a user by ID
+func (s *UserServiceExample) GetUserExample(ctx context.Context, userID pgtype.UUID) (sqlc.User, error) {
+	// Use typed query
+	user, err := s.db.GetUserByID(ctx, userID)
+	if err != nil {
+		return sqlc.User{}, fmt.Errorf("failed to get user: %w", err)
+	}
+
+	// Convert GetUserByIDRow to User
+	return sqlc.User{
+		ID:         user.ID,
+		Email:      user.Email,
+		FirstName:  user.FirstName,
+		LastName:   user.LastName,
+		AvatarUrl:  user.AvatarUrl,
+		IsActive:   user.IsActive,
+		IsVerified: user.IsVerified,
+		LastLogin:  user.LastLogin,
+		CreatedAt:  user.CreatedAt,
+		UpdatedAt:  user.UpdatedAt,
+	}, nil
+}
+
+// SearchUsersExample shows how to search users with pagination
+func (s *UserServiceExample) SearchUsersExample(ctx context.Context, limit, offset int32) ([]sqlc.User, error) {
+	// Use typed query with parameters
+	users, err := s.db.ListUsers(ctx, sqlc.ListUsersParams{
+		Limit:  limit,
+		Offset: offset,
+	})
+	if err != nil {
+		return nil, fmt.Errorf("failed to list users: %w", err)
+	}
+
+	// Convert ListUsersRow to User
+	result := make([]sqlc.User, len(users))
+	for i, user := range users {
+		result[i] = sqlc.User{
+			ID:         user.ID,
+			Email:      user.Email,
+			FirstName:  user.FirstName,
+			LastName:   user.LastName,
+			AvatarUrl:  user.AvatarUrl,
+			IsActive:   user.IsActive,
+			IsVerified: user.IsVerified,
+			LastLogin:  user.LastLogin,
+			CreatedAt:  user.CreatedAt,
+			UpdatedAt:  user.UpdatedAt,
+		}
+	}
+
+	return result, nil
+}
+
+// TransactionExample shows how to use transactions with sqlc
+func (s *UserServiceExample) TransactionExample(ctx context.Context, email, passwordHash string) (sqlc.User, error) {
+	// Start transaction
+	tx, err := s.db.BeginTx(ctx)
+	if err != nil {
+		return sqlc.User{}, fmt.Errorf("failed to begin transaction: %w", err)
+	}
+	defer func() {
+		if err != nil {
+			tx.Rollback()
+		}
+	}()
+
+	// Create user within transaction
+	user, err := tx.CreateUser(ctx, sqlc.CreateUserParams{
+		Email:        email,
+		PasswordHash: passwordHash,
+		IsActive:     &[]bool{true}[0],
+		IsVerified:   &[]bool{false}[0],
+	})
+	if err != nil {
+		return sqlc.User{}, fmt.Errorf("failed to create user in transaction: %w", err)
+	}
+
+	// Update last login within transaction
+	err = tx.UpdateLastLogin(ctx, user.ID)
+	if err != nil {
+		return sqlc.User{}, fmt.Errorf("failed to update last login: %w", err)
+	}
+
+	// Commit transaction
+	if err := tx.Commit(); err != nil {
+		return sqlc.User{}, fmt.Errorf("failed to commit transaction: %w", err)
+	}
+
+	// Convert CreateUserRow to User
+	return sqlc.User{
+		ID:         user.ID,
+		Email:      user.Email,
+		FirstName:  user.FirstName,
+		LastName:   user.LastName,
+		AvatarUrl:  user.AvatarUrl,
+		IsActive:   user.IsActive,
+		IsVerified: user.IsVerified,
+		LastLogin:  user.LastLogin,
+		CreatedAt:  user.CreatedAt,
+		UpdatedAt:  user.UpdatedAt,
+	}, nil
+}