Address PR #1214 code review feedback

- Fix template-expanded URIs not rendering: construct synthetic Resource
  from readState.uri when the URI is absent from the resources list
- Fix non-image blob content rendering raw base64: show placeholder
  message; also handle audio blobs properly
- Hide mimeType display when multiple content items to avoid confusion
- Rename ResourceControls selectedTemplate → selectedTemplateUri for
  consistency with selectedUri and selectedResourceUri

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

clients/web/src/components/groups/ResourceControls/ResourceControls.tsx

@@ -22,7 +22,7 @@ export interface ResourceControlsProps {
   templates: ResourceTemplate[];
   subscriptions: InspectorResourceSubscription[];
   selectedUri?: string;
-  selectedTemplate?: string;
+  selectedTemplateUri?: string;
   listChanged: boolean;
   onRefreshList: () => void;
   onSelectUri: (uri: string) => void;
@@ -46,7 +46,7 @@ export function ResourceControls({
   templates,
   subscriptions,
   selectedUri,
-  selectedTemplate,
+  selectedTemplateUri,
   listChanged,
   onRefreshList,
   onSelectUri,
@@ -137,9 +137,9 @@ export function ResourceControls({
                   <ResourceListItem
                     key={template.uriTemplate}
                     resource={template}
-                    selected={template.uriTemplate === selectedTemplate}
+                    selected={template.uriTemplate === selectedTemplateUri}
                     onClick={() => {
-                      if (template.uriTemplate !== selectedTemplate)
+                      if (template.uriTemplate !== selectedTemplateUri)
                         onSelectTemplate(template.uriTemplate);
                     }}
                   />