fix(hotkeys): block the editor and quick search while a blocking operation runs

Global hotkeys come from Win32, outside the window, so the busy overlay intercepts nothing: Ctrl+Shift+A opened the editor behind it, unreachable. Guarded in openSlideOver and openQuickSearchModal rather than at each trigger - every caller routes through them, and no save path raises the overlay.

js/app.js

@@ -3839,6 +3839,15 @@ const ENTRY_TEMPLATES = {
 // pre-fill the corresponding fields for the new-entry path.
 async function openSlideOver(id, opts) {
     opts = opts || {};
+    // A blocking operation owns the screen (export, sync, rotation). The busy
+    // overlay covers the panel, so the editor would open unreachable behind it
+    // — and the Ctrl+Shift+A hotkey reaches this from outside the window, where
+    // the overlay stops nothing. No save path shows the overlay, so nothing
+    // legitimate opens the editor while it is up.
+    if (isBusy()) {
+        toast('Busy — try again in a moment', 'warning');
+        return false;
+    }
     const isNew = (id == null);
     const e = isNew ? null : state.entries.find(x => x.id === id);
     // Switching to another entry while the current edit has unsaved

js/app.overlays.js

@@ -465,6 +465,13 @@ function endTour() {
 }
 
 function openQuickSearchModal(hideAfter, forFill) {
+    // Same reason as the editor: the hotkey fires from outside the window, so
+    // the busy overlay covering the app stops nothing — the modal would open
+    // behind it, unreachable.
+    if (typeof isBusy === 'function' && isBusy()) {
+        toast('Busy — try again in a moment', 'warning');
+        return;
+    }
     const modal = document.getElementById('quickSearchModal');
     const input = document.getElementById('quickSearchInput');
     modal.classList.remove('is-hidden');