Fix subscriptions loading issues and sidebar link visibility race condition.

- Updated `shimLegacySimplePoolMethods` in `js/nostr/toolkit.js` to correctly handle `nostr-tools` v2 subscription closers (which are functions) in `unsub`. This prevents subscription leaks that were causing relays to reject new requests, leading to empty subscription lists.
- Updated `bootstrapInterface` in `js/index.js` to await `applicationReadyPromise` before attempting to hydrate the sidebar navigation. This fixes a race condition where the sidebar "Subscriptions" link would remain hidden because the application auth state wasn't fully initialized when the sidebar was rendered.

js/index.js

@@ -621,6 +621,12 @@ async function bootstrapInterface() {
   await loadSidebar("components/sidebar.html", "sidebarContainer");
   devLogger.log("Sidebar loaded.");
 
+  try {
+    await applicationReadyPromise;
+  } catch (error) {
+    // fall through
+  }
+
   if (application && typeof application.hydrateSidebarNavigation === "function") {
     try {
       application.hydrateSidebarNavigation();

js/nostr/toolkit.js

@@ -522,7 +522,11 @@ export function shimLegacySimplePoolMethods(pool) {
           }
           closed = true;
           try {
-            closer?.close?.("closed by caller");
+            if (typeof closer === "function") {
+              closer();
+            } else if (closer && typeof closer.close === "function") {
+              closer.close("closed by caller");
+            }
           } catch (error) {
             devLogger.warn("[nostr] Failed to close SimplePool subscription.", error);
           }