data workspace extension batch 2 (#12208)

* work in progress

* load projects in view and test cases

* update scope

* make the sql proj menu available in workspace view

* add extension unit test

* address comments

* fix errors

extensions/data-workspace/src/dataworkspace.d.ts

@@ -0,0 +1,59 @@
+/*---------------------------------------------------------------------------------------------
+ *  Copyright (c) Microsoft Corporation. All rights reserved.
+ *  Licensed under the Source EULA. See License.txt in the project root for license information.
+ *--------------------------------------------------------------------------------------------*/
+
+declare module 'dataworkspace' {
+	import * as vscode from 'vscode';
+	export const enum extension {
+		name = 'Microsoft.data-workspace'
+	}
+
+	/**
+	 * dataworkspace extension
+	 */
+	export interface IExtension {
+		/**
+		 * register a project provider
+		 * @param provider new project provider
+		 * @requires a disposable object, upon disposal, the provider will be unregistered.
+		 */
+		registerProjectProvider(provider: IProjectProvider): vscode.Disposable;
+	}
+
+	/**
+	 * Defines the capabilities of project provider
+	 */
+	export interface IProjectProvider {
+		/**
+		 * Gets the tree data provider for the given project file
+		 * @param projectFilePath The full path of the project file
+		 */
+		getProjectTreeDataProvider(projectFilePath: string): Promise<vscode.TreeDataProvider<any>>;
+
+		/**
+		 * Gets the supported project types
+		 */
+		readonly supportedProjectTypes: IProjectType[];
+	}
+
+	/**
+	 * Defines the project type
+	 */
+	export interface IProjectType {
+		/**
+		 * display name of the project type
+		 */
+		readonly displayName: string;
+
+		/**
+		 * project file extension, e.g. sqlproj
+		 */
+		readonly projectFileExtension: string;
+
+		/**
+		 * Gets the icon path of the project type
+		 */
+		readonly icon: string | vscode.Uri | { light: string | vscode.Uri, dark: string | vscode.Uri }
+	}
+}