Add encrypted LAN sync between MrTerm devices: UDP discovery, X25519 pairing with short authentication code, mutually authenticated AES-256-GCM sessions, last-writer-wins merge with deletions, and per-item opt-in for SSH keys, passwords and VPN configurations

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src/main/store.js

@@ -15,6 +15,10 @@ const DEFAULTS = {
   vpns: [],
   knownHosts: {},
   history: [],
+  // Löschvermerke für die Synchronisation: { c: Collection, id, at }
+  tombstones: [],
+  // LAN-Synchronisation (gerätebezogen, wird selbst nicht synchronisiert)
+  sync: { enabled: false, deviceId: '', deviceName: '', peers: [], share: { keys: [], hosts: [], vpns: [] }, asked: false },
   settings: {
     terminalTheme: 'mrterm',
     fontFamily: 'Cascadia Code, JetBrains Mono, Fira Code, Consolas, monospace',
@@ -124,6 +128,7 @@ class Store {
 
   save() {
     if (this.sealed) return; // Inhalt noch nicht entschlüsselt – nichts überschreiben
+    if (!this.muted) this.onChange?.();
     let json = JSON.stringify(this.data, null, 2);
     if (this.lockEnabled && this.dek) {
       const { language, appTheme, accent } = this.data.settings;
@@ -156,7 +161,20 @@ class Store {
 
   remove(collection, id) {
     this.data[collection] = this.data[collection].filter((x) => x.id !== id);
-    if (collection === 'groups') this.data.hosts.forEach((h) => { if (h.groupId === id) h.groupId = null; });
+    if (collection === 'groups') this.data.hosts.forEach((h) => { if (h.groupId === id) { h.groupId = null; h.updatedAt = Date.now(); } });
+    this.tombstone(collection, id);
+    this.save();
+  }
+
+  // Löschung für andere Geräte vermerken (180 Tage aufbewahren)
+  tombstone(c, id) {
+    const now = Date.now();
+    this.data.tombstones = [...(this.data.tombstones || []).filter((t) => !(t.c === c && t.id === id) && now - t.at < 180 * 864e5), { c, id, at: now }];
+  }
+
+  forgetKnownHost(id) {
+    delete this.data.knownHosts[id];
+    this.tombstone('knownHosts', id);
     this.save();
   }