feat: encrypted-history prompt, incoming-call alerts, message edit, panic button (v1.7.0+11)

P1 key_restore_prompt: offer recovery-key restore right after login
P2 incoming calls: mount overlay in app.dart + detect MSC3401 call.member
   (Element X signalling) — calls were previously invisible
P3 message edit: editMessage/EditMessage + Edit dialog (reactions/delete
   were already wired)
P5 panic button: new feature/panic module — hold-to-send alert text +
   m.location to a configured room; alert sent before geolocation so a
   denied permission never blocks it

All verified end-to-end in headless Chromium against production build.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

lib/features/profile/presentation/key_restore_prompt.dart

@@ -0,0 +1,80 @@
+// Version: 1.0.0 | Created: 2026-07-04
+// Post-login prompt: if the account has secret storage (key backup) and this
+// fresh device cannot read encrypted history yet, offer the recovery-key
+// restore straight away instead of leaving it buried in Profile > Security.
+//
+// Shown at most once per login session. "Later" keeps the old behaviour
+// (restore manually from the Profile tab).
+
+import 'dart:async';
+
+import 'package:flutter/material.dart';
+import 'package:matrix/matrix.dart';
+
+import 'key_restore_dialog.dart';
+
+bool _promptedThisSession = false;
+
+/// Reset when a new login happens (called from the login flow if needed).
+void resetKeyRestorePrompt() => _promptedThisSession = false;
+
+/// Checks whether the freshly logged-in session needs a key restore and,
+/// if so, asks the user. Safe to call multiple times; only fires once.
+Future<void> maybePromptKeyRestore(BuildContext context, Client client) async {
+  if (_promptedThisSession) return;
+  _promptedThisSession = true;
+
+  try {
+    // Wait for the first sync so account data (secret storage config) exists.
+    if (client.prevBatch == null) {
+      await client.onSync.stream.first.timeout(const Duration(seconds: 30));
+    }
+  } on TimeoutException {
+    debugPrint('[KeyRestorePrompt] first sync timed out — skipping');
+    return;
+  }
+
+  final enc = client.encryption;
+  if (enc == null) return;
+
+  // No secret storage on the account → nothing to restore from.
+  final hasSecretStorage =
+      client.accountData.containsKey('m.secret_storage.default_key');
+  if (!hasSecretStorage) return;
+
+  // Keys already cached (or session verified) → nothing to do.
+  var cached = false;
+  try {
+    cached = await enc.keyManager.isCached();
+  } on Exception catch (e) {
+    debugPrint('[KeyRestorePrompt] isCached failed: $e');
+  }
+  if (cached && !client.isUnknownSession) return;
+
+  if (!context.mounted) return;
+
+  final wantsRestore = await showDialog<bool>(
+    context: context,
+    builder: (ctx) => AlertDialog(
+      title: const Text('Restore encrypted messages?'),
+      content: const Text(
+        'This device cannot read your older encrypted messages yet. '
+        'Enter your recovery key now to unlock them, or do it later '
+        'from Profile > Security & Privacy.',
+      ),
+      actions: [
+        TextButton(
+          onPressed: () => Navigator.of(ctx).pop(false),
+          child: const Text('Later'),
+        ),
+        FilledButton(
+          onPressed: () => Navigator.of(ctx).pop(true),
+          child: const Text('Enter recovery key'),
+        ),
+      ],
+    ),
+  );
+
+  if (wantsRestore != true || !context.mounted) return;
+  await showKeyRestoreDialog(context, client);
+}