ui: Fix handling of MCP resource template parameters (ggml-org#23117)

* Fix handling of MCP resource template parameters

* Fix formatting for uri-template.test.ts

---------

Co-authored-by: kuba <kuba@laptop.local.net>

Author: kubawoo

tools/ui/src/lib/utils/uri-template.ts

@@ -160,7 +160,7 @@ export function expandTemplate(template: string, values: Record<string, string>)
 								(name: string, i: number) =>
 									`${encodeURIComponent(name)}=${encodeURIComponent(expandedParts[i])}`
 							)
-							.join(URI_TEMPLATE_SEPARATORS.COMMA)
+							.join(URI_TEMPLATE_SEPARATORS.QUERY_CONTINUATION)
 					);
 				case URI_TEMPLATE_OPERATORS.FORM_CONTINUATION:
 					// Form-style query continuation

tools/ui/tests/unit/uri-template.test.ts

@@ -107,6 +107,14 @@ describe('expandTemplate', () => {
 		expect(result).toBe('http://example.com?q=search%20term');
 	});
 
+	it('expands multiple query parameters', () => {
+		const result = expandTemplate('http://example.com{?q,sort}', {
+			q: 'search term',
+			sort: 'descending'
+		});
+		expect(result).toBe('http://example.com?q=search%20term&sort=descending');
+	});
+
 	it('keeps static parts unchanged', () => {
 		const result = expandTemplate('http://example.com/static', {});
 		expect(result).toBe('http://example.com/static');