Add widget to change how content is pasted (#181290)

* Add widget to change how content is pasted

For #30066

This adds a widget that lets you change how content is pasted if there are multiple ways it could be pasted

To do this, I've made the post drop widget generic and reused it for pasting too

* Update types

* More code deduplication

extensions/markdown-language-features/src/languageFeatures/copyFiles/copyPaste.ts

@@ -46,7 +46,7 @@ class PasteEditProvider implements vscode.DocumentPasteEditProvider {
 		}
 
 		const snippet = await tryGetUriListSnippet(document, dataTransfer, token);
-		return snippet ? new vscode.DocumentPasteEdit(snippet.snippet) : undefined;
+		return snippet ? new vscode.DocumentPasteEdit(snippet.snippet, snippet.label) : undefined;
 	}
 
 	private async _makeCreateImagePasteEdit(document: vscode.TextDocument, file: vscode.DataTransferFile, token: vscode.CancellationToken): Promise<vscode.DocumentPasteEdit | undefined> {
@@ -55,7 +55,7 @@ class PasteEditProvider implements vscode.DocumentPasteEditProvider {
 			const workspaceFolder = vscode.workspace.getWorkspaceFolder(file.uri);
 			if (workspaceFolder) {
 				const snippet = createUriListSnippet(document, [file.uri]);
-				return snippet ? new vscode.DocumentPasteEdit(snippet.snippet) : undefined;
+				return snippet ? new vscode.DocumentPasteEdit(snippet.snippet, snippet.label) : undefined;
 			}
 		}
 
@@ -73,7 +73,7 @@ class PasteEditProvider implements vscode.DocumentPasteEditProvider {
 		const workspaceEdit = new vscode.WorkspaceEdit();
 		workspaceEdit.createFile(uri, { contents: file });
 
-		const pasteEdit = new vscode.DocumentPasteEdit(snippet.snippet);
+		const pasteEdit = new vscode.DocumentPasteEdit(snippet.snippet, snippet.label);
 		pasteEdit.additionalEdit = workspaceEdit;
 		return pasteEdit;
 	}