Rename indexed dbs with positron prefix (#5035)

- Addresses: #4864
- updates the prefixes for web IndexedDB databases and stores to use
`positron` instead of `vscode`
- we don't delete the existing stores that are prefixed with `vscode`

I've done some testing on a dev build of Server Web on Mac and a local
release build of Positron on Workbench on Ubuntu 24.

### QA Notes

- this change impacts Positron Web / Server Web only
- the data stores are working if:
- you're seeing the renamed databases and stores in Developer Tools >
Application > Storage > IndexedDB
- the layout state is being persisted when you close and reopen Positron
in the same browser; for example:
        1. Open up a folder in Positron Web / Server Web
        2. Command Prompt > View: Toggle Zen Mode
        3. Close the browser
4. Open up the same folder in the same browser in Positron Web / Server
Web
        5. You should still be in Zen Mode

src/vs/workbench/browser/web.main.ts

@@ -459,11 +459,15 @@ export class BrowserMain extends Disposable {
 
 		// IndexedDB is used for logging and user data
 		let indexedDB: IndexedDB | undefined;
-		const userDataStore = 'vscode-userdata-store';
-		const logsStore = 'vscode-logs-store';
-		const handlesStore = 'vscode-filehandles-store';
+		// --- Start Positron ---
+		const userDataStore = 'positron-userdata-store';
+		const logsStore = 'positron-logs-store';
+		const handlesStore = 'positron-filehandles-store';
+		// --- End Positron ---
 		try {
-			indexedDB = await IndexedDB.create('vscode-web-db', 3, [userDataStore, logsStore, handlesStore]);
+			// --- Start Positron ---
+			indexedDB = await IndexedDB.create('positron-web-db', 3, [userDataStore, logsStore, handlesStore]);
+			// --- End Positron ---
 
 			// Close onWillShutdown
 			this.onWillShutdownDisposables.add(toDisposable(() => indexedDB?.close()));

src/vs/workbench/services/storage/browser/storageService.ts

@@ -339,7 +339,9 @@ export class IndexedDBStorageDatabase extends Disposable implements IIndexedDBSt
 		}
 	}
 
-	private static readonly STORAGE_DATABASE_PREFIX = 'vscode-web-state-db-';
+	// --- Start Positron ---
+	private static readonly STORAGE_DATABASE_PREFIX = 'positron-web-state-db-';
+	// --- End Positron ---
 	private static readonly STORAGE_OBJECT_STORE = 'ItemTable';
 
 	private readonly _onDidChangeItemsExternal = this._register(new Emitter<IStorageItemsChangeEvent>());