[ui] route all native alert()/confirm() through the site notification system

Every browser alert()/confirm() now uses the app's UI instead of native dialogs
(no prompt() existed). Two new pieces:

- js/ui/confirmDialog.js — showConfirm(message, opts) -> Promise<boolean>, a styled
  `bv-modal modal-always-on-top` dialog (Confirm/Cancel/backdrop/Escape; danger variant
  focuses Cancel). Importable anywhere, so future confirmations use it too. It stacks
  above other modals and is typable thanks to the recent stacked-modal focus fix.
- js/ui/appNotify.js — notifyError/notifyStatus/notifySuccess routing to the app's
  NotificationController, for modules without a local showError; re-exports showConfirm.

Migrated: UploadModal (10 alert -> this.showError, 1 confirm), subscriptionHistory
(3 alert -> notify*, 1 confirm), MyVideosController (2), ProfileStorage/Wallet/Relay
controllers, profileModalController (2), settingsRestorePrompt (default confirm now
showConfirm), nostr/client deleteAllVersions. confirmSyncOverwrite helpers made async
(syncConflict already awaits confirmOverwrite).

Tests: tests/confirm-dialog.test.mjs (6 — confirm/cancel/backdrop/Escape resolution,
DOM cleanup, danger focus, no-DOM fallback). Build + lint clean; affected suites green.
(Note: build/lint don't parse JS — caught a multi-line-import split + a wrong import
path via module-import checks.)

Co-Authored-By: Claude Opus 4.8 <[email protected]>

js/ui/profileModal/ProfileWalletController.js

@@ -1,4 +1,5 @@
 import { devLogger } from "../../utils/logger.js";
+import { showConfirm } from "../confirmDialog.js";
 import { NWC_URI_SCHEME } from "../profileModalContract.js";
 import { createWalletSyncService } from "../../services/walletSyncService.js";
 import { runWalletZappabilityCheck } from "./walletZappabilityCheck.js";
@@ -104,12 +105,10 @@ export class ProfileWalletController {
   }
 
   confirmSyncOverwrite() {
-    if (typeof window === "undefined" || typeof window.confirm !== "function") {
-      return true;
-    }
-    return window.confirm(
+    return showConfirm(
       "A newer copy of your wallet connection is on your account (changed on " +
-        "another device). Overwrite it with this one?"
+        "another device). Overwrite it with this one?",
+      { confirmLabel: "Overwrite", danger: true },
     );
   }
 
@@ -158,14 +157,12 @@ export class ProfileWalletController {
     try {
       if (enabled) {
         // Spending capability — require explicit confirmation before publishing.
-        const confirmed =
-          typeof window !== "undefined" && typeof window.confirm === "function"
-            ? window.confirm(
-                "This publishes an ENCRYPTED copy of your wallet connection to public relays.\n\n" +
-                  "A wallet connect URI can SPEND from your wallet. Anyone who controls your " +
-                  "Nostr key could decrypt this and spend from this wallet.\n\nContinue?"
-              )
-            : true;
+        const confirmed = await showConfirm(
+          "This publishes an ENCRYPTED copy of your wallet connection to public relays.\n\n" +
+            "A wallet connect URI can SPEND from your wallet. Anyone who controls your " +
+            "Nostr key could decrypt this and spend from this wallet.\n\nContinue?",
+          { confirmLabel: "Publish", danger: true },
+        );
         if (!confirmed) {
           if (this.walletSyncToggle instanceof HTMLInputElement) {
             this.walletSyncToggle.checked = false;