refactor(db): use version string as primary key for ConfigVersion

-transition `of_config_versions` primary key from `id` to `version` string.
-add database migration files `202606270001_make_version_primary_key.sql` for PostgreSQL and SQLite.
-introduce AfterFind/AfterCreate GORM hooks to preserve JSON backward compatibility.
-refactor API controllers, logics, and front-end typescript definitions to receive `string` parameter.

internal/apps/openflare/flared/helpers.go

@@ -5,16 +5,13 @@ package flared
 
 import (
 	"context"
-	"errors"
 	"fmt"
 	"net"
 	"strconv"
 	"strings"
 
 	"github.com/Rain-kl/Wavelet/internal/apps/openflare/relay"
-	"github.com/Rain-kl/Wavelet/internal/db"
 	"github.com/Rain-kl/Wavelet/internal/model"
-	"gorm.io/gorm"
 )
 
 const (
@@ -22,15 +19,6 @@ const (
 	defaultTunnelTargetPort = 80
 )
 
-type configVersionRow struct {
-	Version  string `gorm:"column:version"`
-	Checksum string `gorm:"column:checksum"`
-}
-
-func (configVersionRow) TableName() string {
-	return "of_config_versions"
-}
-
 func normalizeReleaseChannel(channel string) string {
 	if strings.ToLower(strings.TrimSpace(channel)) == "preview" {
 		return "preview"
@@ -63,16 +51,7 @@ func normalizeFlaredHeartbeatPayload(payload HeartbeatPayload) HeartbeatPayload
 }
 
 func getActiveConfigMeta(ctx context.Context) (*ActiveConfigMeta, error) {
-	conn := db.DB(ctx)
-	if conn == nil {
-		return nil, errors.New("database not initialized")
-	}
-	if !conn.Migrator().HasTable(&configVersionRow{}) {
-		return nil, gorm.ErrRecordNotFound
-	}
-
-	var version configVersionRow
-	err := conn.Where("is_active = ?", true).Order("id desc").First(&version).Error
+	version, err := model.GetActiveConfigVersion(ctx)
 	if err != nil {
 		return nil, err
 	}

internal/apps/openflare/flared/logics.go

@@ -98,7 +98,7 @@ func GetTunnelConfig(ctx context.Context, node *model.OpenFlareNode) (*TunnelCon
 		return nil, fmt.Errorf("node is nil")
 	}
 
-	activeVersion, err := getActiveConfigVersion(ctx)
+	activeVersion, err := getActiveConfigMeta(ctx)
 	if err != nil {
 		return nil, fmt.Errorf("no active config version: %w", err)
 	}
@@ -232,21 +232,6 @@ func updateFlaredNodeFromApplyLogTx(tx *gorm.DB, payload ApplyLogPayload, now ti
 	return tx.Model(&node).Select("status", "last_seen_at", "current_version", "last_error").Updates(&node).Error
 }
 
-func getActiveConfigVersion(ctx context.Context) (*configVersionRow, error) {
-	conn := db.DB(ctx)
-	if conn == nil {
-		return nil, errors.New("database not initialized")
-	}
-	if !conn.Migrator().HasTable(&configVersionRow{}) {
-		return nil, gorm.ErrRecordNotFound
-	}
-	var version configVersionRow
-	if err := conn.Where("is_active = ?", true).Order("id desc").First(&version).Error; err != nil {
-		return nil, err
-	}
-	return &version, nil
-}
-
 func normalizeApplyLogPayload(payload ApplyLogPayload) ApplyLogPayload {
 	payload.NodeID = strings.TrimSpace(payload.NodeID)
 	payload.Version = strings.TrimSpace(payload.Version)

internal/apps/openflare/flared/observability_test.go

@@ -27,6 +27,7 @@ func setupFlaredObservabilityTestDB(t *testing.T) func() {
 		&model.OpenFlareNode{},
 		&model.OpenFlareHealthEvent{},
 		&model.SystemConfig{},
+		&model.ConfigVersion{},
 	))
 
 	db.SetDB(sqliteDB)