finish SwiftData migration with @Query views

- Drive chat list, timeline and forward picker from SwiftData @Query
  instead of AppModel's in-memory arrays; inject the per-account
  ModelContext from RootView with an in-memory fallback.
- Physically delete locally deleted messages (context.delete) and
  purge rows marked deleted by older builds on store open, so @Query
  views never resurrect them.
- Delete the legacy JSON snapshot only after a successful import save
  and restore the completeUntilFirstUserAuthentication data protection
  attribute on the store file.
- Mirror the old ChatArchive tolerant decoding in LegacyArchiveImporter
  so snapshots from older schema versions (missing reactions,
  isGroupMessage, roster fields) still import.
- Cover the new behaviour in ArchiveStoreTests and guard it with new
  verify.sh invariants; update AGENTS.md, ARCHITECTURE.md and
  SECURITY.md.

Sources/Shared/UI/ForwardMessageView.swift

@@ -1,3 +1,4 @@
+import SwiftData
 import SwiftUI
 
 @MainActor
@@ -10,6 +11,9 @@ struct ForwardMessageView: View {
     @State private var destinationJID = ""
     @State private var isForwarding = false
 
+    /// SwiftData-backed destination list, ordered like the main chat list.
+    @Query private var conversations: [Conversation]
+
     init(
         model: AppModel,
         messages: [ChatMessage],
@@ -18,6 +22,11 @@ struct ForwardMessageView: View {
         _model = ObservedObject(wrappedValue: model)
         self.messages = messages.filter(\.canBeForwarded)
         self.onComplete = onComplete
+        _conversations = Query(
+            sort: [
+                SortDescriptor(\Conversation.lastActivity, order: .reverse),
+            ]
+        )
     }
 
     var body: some View {
@@ -39,9 +48,9 @@ struct ForwardMessageView: View {
                     }
                 }
 
-                if !model.conversations.isEmpty {
+                if !orderedConversations.isEmpty {
                     Section("Чаты") {
-                        ForEach(model.conversations) { conversation in
+                        ForEach(orderedConversations) { conversation in
                             Button {
                                 forward(to: conversation.jid)
                             } label: {
@@ -105,6 +114,14 @@ struct ForwardMessageView: View {
 #endif
     }
 
+    /// Pinned-first ordering, matching the main chat list.
+    private var orderedConversations: [Conversation] {
+        conversations.sorted { lhs, rhs in
+            if lhs.isPinned != rhs.isPinned { return lhs.isPinned }
+            return lhs.lastActivity > rhs.lastActivity
+        }
+    }
+
     private func forward(to jid: String) {
         guard !isForwarding, !messages.isEmpty else { return }
         isForwarding = true