feat(cli): add dbx node packages

packages/node-core/src/backend.ts

@@ -0,0 +1,39 @@
+import {
+  addConnection as desktopAddConnection,
+  findConnection as desktopFindConnection,
+  loadConnections as desktopLoadConnections,
+  removeConnection as desktopRemoveConnection,
+} from "./connections.js";
+import {
+  describeTable as desktopDescribeTable,
+  executeQuery as desktopExecuteQuery,
+  listTables as desktopListTables,
+} from "./database.js";
+import type { ConnectionConfig } from "./connections.js";
+import type { ColumnInfo, QueryOptions, QueryResult, TableInfo } from "./database.js";
+
+export interface Backend {
+  loadConnections(): Promise<ConnectionConfig[]>;
+  findConnection(name: string): Promise<ConnectionConfig | undefined>;
+  addConnection(config: Omit<ConnectionConfig, "id">): Promise<ConnectionConfig>;
+  removeConnection(name: string): Promise<boolean>;
+  listTables(config: ConnectionConfig, schema?: string): Promise<TableInfo[]>;
+  describeTable(config: ConnectionConfig, table: string, schema?: string): Promise<ColumnInfo[]>;
+  executeQuery(config: ConnectionConfig, sql: string, options?: QueryOptions): Promise<QueryResult>;
+}
+
+export async function createBackend(env: NodeJS.ProcessEnv = process.env): Promise<Backend> {
+  if (env.DBX_WEB_URL) {
+    return await import("./web-backend.js");
+  }
+
+  return {
+    loadConnections: desktopLoadConnections,
+    findConnection: desktopFindConnection,
+    addConnection: desktopAddConnection,
+    removeConnection: desktopRemoveConnection,
+    listTables: desktopListTables,
+    describeTable: desktopDescribeTable,
+    executeQuery: desktopExecuteQuery,
+  };
+}