fix: strip trailing slash from VS Code OAuth redirect URI

vscode.Uri.toString() adds a trailing slash, causing a mismatch with
the OAuth provider's verbatim redirect URI check.

Author: clavery

.changeset/fix-vscode-oauth-redirect-uri.md

@@ -0,0 +1,5 @@
+---
+'b2c-vs-extension': patch
+---
+
+Fix OAuth redirect URI trailing slash mismatch that caused authentication failures in VS Code

packages/b2c-vs-extension/src/config-provider.ts

@@ -248,7 +248,7 @@ export class B2CExtensionConfig implements vscode.Disposable {
     const externalUri = await vscode.env.asExternalUri(localUri);
 
     return {
-      redirectUri: process.env.SFCC_REDIRECT_URI || externalUri.toString(/* skipEncoding */ true),
+      redirectUri: (process.env.SFCC_REDIRECT_URI || externalUri.toString(/* skipEncoding */ true)).replace(/\/$/, ''),
       openBrowser: async (url: string) => {
         await vscode.env.openExternal(vscode.Uri.parse(url));
       },