refactor(layout): relocate go.mod to backend/ and clean import paths to module root

- Relocated go.mod and go.sum into backend/ root directory
- Stripped redundant backend/ segments from all Go imports (github.com/Rain-kl/Wavelet/...)
- Unified Makefile, swagger, and build-test to execute in backend/ module context
- Ensured 100% build-test, code-check, format, and swagger pass

backend/cmd/all.go

@@ -8,7 +8,7 @@ package cmd
 import (
 	"log"
 
-	"github.com/Rain-kl/Wavelet/backend/core"
+	"github.com/Rain-kl/Wavelet/core"
 	"github.com/spf13/cobra"
 )
 

backend/cmd/api.go

@@ -7,7 +7,7 @@ package cmd
 import (
 	"log"
 
-	"github.com/Rain-kl/Wavelet/backend/core"
+	"github.com/Rain-kl/Wavelet/core"
 	"github.com/spf13/cobra"
 )
 

backend/cmd/app.go

@@ -10,24 +10,24 @@ import (
 	"log"
 	"time"
 
-	"github.com/Rain-kl/Wavelet/backend/core"
-	"github.com/Rain-kl/Wavelet/backend/core/contracts"
-	"github.com/Rain-kl/Wavelet/backend/pkg/config"
-	"github.com/Rain-kl/Wavelet/backend/plugins/domain/admin"
-	"github.com/Rain-kl/Wavelet/backend/plugins/domain/auth"
-	"github.com/Rain-kl/Wavelet/backend/plugins/domain/cap"
-	"github.com/Rain-kl/Wavelet/backend/plugins/domain/message_gateway"
-	"github.com/Rain-kl/Wavelet/backend/plugins/domain/risk_control"
-	"github.com/Rain-kl/Wavelet/backend/plugins/domain/system"
-	"github.com/Rain-kl/Wavelet/backend/plugins/domain/upload"
-	"github.com/Rain-kl/Wavelet/backend/plugins/domain/user"
-	"github.com/Rain-kl/Wavelet/backend/plugins/drivers/driver_asynq_cron"
-	"github.com/Rain-kl/Wavelet/backend/plugins/drivers/driver_asynq_worker"
-	"github.com/Rain-kl/Wavelet/backend/plugins/drivers/driver_http"
-	"github.com/Rain-kl/Wavelet/backend/plugins/infra/cache"
-	infradb "github.com/Rain-kl/Wavelet/backend/plugins/infra/database"
-	"github.com/Rain-kl/Wavelet/backend/plugins/infra/logger"
-	"github.com/Rain-kl/Wavelet/backend/plugins/infra/storage"
+	"github.com/Rain-kl/Wavelet/core"
+	"github.com/Rain-kl/Wavelet/core/contracts"
+	"github.com/Rain-kl/Wavelet/pkg/config"
+	"github.com/Rain-kl/Wavelet/plugins/domain/admin"
+	"github.com/Rain-kl/Wavelet/plugins/domain/auth"
+	"github.com/Rain-kl/Wavelet/plugins/domain/cap"
+	"github.com/Rain-kl/Wavelet/plugins/domain/message_gateway"
+	"github.com/Rain-kl/Wavelet/plugins/domain/risk_control"
+	"github.com/Rain-kl/Wavelet/plugins/domain/system"
+	"github.com/Rain-kl/Wavelet/plugins/domain/upload"
+	"github.com/Rain-kl/Wavelet/plugins/domain/user"
+	"github.com/Rain-kl/Wavelet/plugins/drivers/driver_asynq_cron"
+	"github.com/Rain-kl/Wavelet/plugins/drivers/driver_asynq_worker"
+	"github.com/Rain-kl/Wavelet/plugins/drivers/driver_http"
+	"github.com/Rain-kl/Wavelet/plugins/infra/cache"
+	infradb "github.com/Rain-kl/Wavelet/plugins/infra/database"
+	"github.com/Rain-kl/Wavelet/plugins/infra/logger"
+	"github.com/Rain-kl/Wavelet/plugins/infra/storage"
 	"github.com/pressly/goose/v3"
 	goosedb "github.com/pressly/goose/v3/database"
 )

backend/cmd/app_test.go

@@ -9,7 +9,7 @@ import (
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 
-	"github.com/Rain-kl/Wavelet/backend/core"
+	"github.com/Rain-kl/Wavelet/core"
 )
 
 func TestNewWaveletAppProfiles(t *testing.T) {

backend/cmd/banner.go

@@ -12,8 +12,8 @@ import (
 	"runtime"
 	"strings"
 
-	"github.com/Rain-kl/Wavelet/backend/pkg/buildinfo"
-	"github.com/Rain-kl/Wavelet/backend/pkg/config"
+	"github.com/Rain-kl/Wavelet/pkg/buildinfo"
+	"github.com/Rain-kl/Wavelet/pkg/config"
 )
 
 //nolint:unused // startup banner formatting utilities

backend/cmd/banner_test.go

@@ -7,8 +7,8 @@ import (
 	"strings"
 	"testing"
 
-	"github.com/Rain-kl/Wavelet/backend/pkg/buildinfo"
-	"github.com/Rain-kl/Wavelet/backend/pkg/config"
+	"github.com/Rain-kl/Wavelet/pkg/buildinfo"
+	"github.com/Rain-kl/Wavelet/pkg/config"
 )
 
 func TestFormatStartupBanner(t *testing.T) {

backend/cmd/reset_passwd.go

@@ -13,10 +13,10 @@ import (
 	"os"
 	"strings"
 
-	userdomain "github.com/Rain-kl/Wavelet/backend/plugins/domain/user"
-	"github.com/Rain-kl/Wavelet/backend/plugins/infra/database"
+	userdomain "github.com/Rain-kl/Wavelet/plugins/domain/user"
+	"github.com/Rain-kl/Wavelet/plugins/infra/database"
 
-	"github.com/Rain-kl/Wavelet/backend/plugins/domain/auth"
+	"github.com/Rain-kl/Wavelet/plugins/domain/auth"
 	"github.com/spf13/cobra"
 	"gorm.io/gorm"
 )

backend/cmd/reset_passwd_test.go

@@ -10,8 +10,8 @@ import (
 	"testing"
 	"time"
 
-	"github.com/Rain-kl/Wavelet/backend/pkg/testhelper"
-	userdomain "github.com/Rain-kl/Wavelet/backend/plugins/domain/user"
+	"github.com/Rain-kl/Wavelet/pkg/testhelper"
+	userdomain "github.com/Rain-kl/Wavelet/plugins/domain/user"
 )
 
 func TestResetPasswdCmd_WithUserAndPassword(t *testing.T) {

backend/cmd/root.go

@@ -9,10 +9,10 @@ import (
 	"log"
 	"time"
 
-	"github.com/Rain-kl/Wavelet/backend/pkg/buildinfo"
-	"github.com/Rain-kl/Wavelet/backend/pkg/config"
-	"github.com/Rain-kl/Wavelet/backend/pkg/logger"
-	"github.com/Rain-kl/Wavelet/backend/pkg/trace"
+	"github.com/Rain-kl/Wavelet/pkg/buildinfo"
+	"github.com/Rain-kl/Wavelet/pkg/config"
+	"github.com/Rain-kl/Wavelet/pkg/logger"
+	"github.com/Rain-kl/Wavelet/pkg/trace"
 	"github.com/spf13/cobra"
 )
 

backend/cmd/scheduler.go

@@ -7,7 +7,7 @@ package cmd
 import (
 	"log"
 
-	"github.com/Rain-kl/Wavelet/backend/core"
+	"github.com/Rain-kl/Wavelet/core"
 	"github.com/spf13/cobra"
 )
 

backend/cmd/worker.go

@@ -7,7 +7,7 @@ package cmd
 import (
 	"log"
 
-	"github.com/Rain-kl/Wavelet/backend/core"
+	"github.com/Rain-kl/Wavelet/core"
 	"github.com/spf13/cobra"
 )