✨ feat(sync): 新增 SQL 结果集数据同步能力

- 同步引擎新增查询结果集同步分支，支持单目标表差异分析、预览与执行
- 数据同步工作台增加 SQL 结果集模式，并补充目标表与查询校验
- 补充后端同步链路与前端请求构造回归测试，并更新 backlog 记录

Fixes #321

internal/sync/source_query_sync_test.go

@@ -0,0 +1,177 @@
+package sync
+
+import (
+	"GoNavi-Wails/internal/connection"
+	"GoNavi-Wails/internal/db"
+	"reflect"
+	"testing"
+)
+
+type fakeQuerySyncTargetDB struct {
+	fakeMigrationDB
+	appliedTable   string
+	appliedChanges connection.ChangeSet
+}
+
+func (f *fakeQuerySyncTargetDB) ApplyChanges(tableName string, changes connection.ChangeSet) error {
+	f.appliedTable = tableName
+	f.appliedChanges = changes
+	return nil
+}
+
+var _ db.BatchApplier = (*fakeQuerySyncTargetDB)(nil)
+
+func TestAnalyze_SourceQueryUsesQueryResultAsSourceDataset(t *testing.T) {
+	sourceDB := &fakeMigrationDB{
+		columns: map[string][]connection.ColumnDefinition{
+			"app.users": {
+				{Name: "id", Type: "bigint", Nullable: "NO", Key: "PRI"},
+				{Name: "name", Type: "varchar(64)", Nullable: "YES"},
+			},
+		},
+		queryData: map[string][]map[string]interface{}{
+			"SELECT id, name FROM active_users": {
+				{"id": 1, "name": "Alice New"},
+				{"id": 2, "name": "Bob"},
+			},
+		},
+	}
+	targetDB := &fakeQuerySyncTargetDB{
+		fakeMigrationDB: fakeMigrationDB{
+			columns: map[string][]connection.ColumnDefinition{
+				"app.users": {
+					{Name: "id", Type: "bigint", Nullable: "NO", Key: "PRI"},
+					{Name: "name", Type: "varchar(64)", Nullable: "YES"},
+				},
+			},
+			queryData: map[string][]map[string]interface{}{
+				"SELECT * FROM `app`.`users`": {
+					{"id": 1, "name": "Alice Old"},
+					{"id": 3, "name": "Carol"},
+				},
+			},
+		},
+	}
+
+	oldFactory := newSyncDatabase
+	defer func() { newSyncDatabase = oldFactory }()
+	callCount := 0
+	newSyncDatabase = func(dbType string) (db.Database, error) {
+		callCount++
+		if callCount == 1 {
+			return sourceDB, nil
+		}
+		return targetDB, nil
+	}
+
+	engine := NewSyncEngine(Reporter{})
+	result := engine.Analyze(SyncConfig{
+		SourceConfig: connection.ConnectionConfig{Type: "mysql", Database: "app"},
+		TargetConfig: connection.ConnectionConfig{Type: "mysql", Database: "app"},
+		Tables:       []string{"users"},
+		Mode:         "insert_update",
+		SourceQuery:  "SELECT id, name FROM active_users",
+	})
+
+	if !result.Success {
+		t.Fatalf("Analyze 返回失败: %+v", result)
+	}
+	if len(result.Tables) != 1 {
+		t.Fatalf("expected one table summary, got %d", len(result.Tables))
+	}
+
+	summary := result.Tables[0]
+	if summary.PKColumn != "id" {
+		t.Fatalf("expected PKColumn=id, got %q", summary.PKColumn)
+	}
+	if !summary.CanSync {
+		t.Fatalf("expected summary can sync, got %+v", summary)
+	}
+	if summary.Inserts != 1 || summary.Updates != 1 || summary.Deletes != 1 {
+		t.Fatalf("unexpected diff summary: %+v", summary)
+	}
+}
+
+func TestRunSync_SourceQueryAppliesDiffAgainstTargetTable(t *testing.T) {
+	sourceDB := &fakeMigrationDB{
+		columns: map[string][]connection.ColumnDefinition{
+			"app.users": {
+				{Name: "id", Type: "bigint", Nullable: "NO", Key: "PRI"},
+				{Name: "name", Type: "varchar(64)", Nullable: "YES"},
+			},
+		},
+		queryData: map[string][]map[string]interface{}{
+			"SELECT id, name FROM active_users": {
+				{"id": 1, "name": "Alice New"},
+				{"id": 2, "name": "Bob"},
+			},
+		},
+	}
+	targetDB := &fakeQuerySyncTargetDB{
+		fakeMigrationDB: fakeMigrationDB{
+			columns: map[string][]connection.ColumnDefinition{
+				"app.users": {
+					{Name: "id", Type: "bigint", Nullable: "NO", Key: "PRI"},
+					{Name: "name", Type: "varchar(64)", Nullable: "YES"},
+				},
+			},
+			queryData: map[string][]map[string]interface{}{
+				"SELECT * FROM `app`.`users`": {
+					{"id": 1, "name": "Alice Old"},
+					{"id": 3, "name": "Carol"},
+				},
+			},
+		},
+	}
+
+	oldFactory := newSyncDatabase
+	defer func() { newSyncDatabase = oldFactory }()
+	callCount := 0
+	newSyncDatabase = func(dbType string) (db.Database, error) {
+		callCount++
+		if callCount == 1 {
+			return sourceDB, nil
+		}
+		return targetDB, nil
+	}
+
+	engine := NewSyncEngine(Reporter{})
+	result := engine.RunSync(SyncConfig{
+		SourceConfig: connection.ConnectionConfig{Type: "mysql", Database: "app"},
+		TargetConfig: connection.ConnectionConfig{Type: "mysql", Database: "app"},
+		Tables:       []string{"users"},
+		Mode:         "insert_update",
+		SourceQuery:  "SELECT id, name FROM active_users",
+		TableOptions: map[string]TableOptions{
+			"users": {Insert: true, Update: true, Delete: true},
+		},
+	})
+
+	if !result.Success {
+		t.Fatalf("RunSync 返回失败: %+v", result)
+	}
+	if result.TablesSynced != 1 || result.RowsInserted != 1 || result.RowsUpdated != 1 || result.RowsDeleted != 1 {
+		t.Fatalf("unexpected sync result: %+v", result)
+	}
+	if targetDB.appliedTable != "users" {
+		t.Fatalf("expected applied table users, got %q", targetDB.appliedTable)
+	}
+
+	wantInserts := []map[string]interface{}{{"id": 2, "name": "Bob"}}
+	if !reflect.DeepEqual(targetDB.appliedChanges.Inserts, wantInserts) {
+		t.Fatalf("unexpected inserts: got=%v want=%v", targetDB.appliedChanges.Inserts, wantInserts)
+	}
+
+	wantUpdates := []connection.UpdateRow{{
+		Keys:   map[string]interface{}{"id": 1},
+		Values: map[string]interface{}{"name": "Alice New"},
+	}}
+	if !reflect.DeepEqual(targetDB.appliedChanges.Updates, wantUpdates) {
+		t.Fatalf("unexpected updates: got=%v want=%v", targetDB.appliedChanges.Updates, wantUpdates)
+	}
+
+	wantDeletes := []map[string]interface{}{{"id": 3}}
+	if !reflect.DeepEqual(targetDB.appliedChanges.Deletes, wantDeletes) {
+		t.Fatalf("unexpected deletes: got=%v want=%v", targetDB.appliedChanges.Deletes, wantDeletes)
+	}
+}