fix: add photo_download_rx channel and fix account switcher nav tests

Add UnboundedReceiver for background photo downloads to App state,
reset it on close_chat. Fix account_switcher tests to navigate past
all accounts dynamically instead of assuming single account.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/app/methods/navigation.rs

@@ -83,6 +83,11 @@ impl<T: TdClientTrait> NavigationMethods<T> for App<T> {
         self.message_scroll_offset = 0;
         self.last_typing_sent = None;
         self.pending_chat_init = None;
+        // Останавливаем фоновую загрузку фото (drop receiver)
+        #[cfg(feature = "images")]
+        {
+            self.photo_download_rx = None;
+        }
         // Сбрасываем состояние чата в нормальный режим
         self.chat_state = ChatState::Normal;
         self.input_mode = InputMode::Normal;

src/app/mod.rs

@@ -128,8 +128,12 @@ pub struct App<T: TdClientTrait = TdClient> {
     pub current_account_name: String,
     /// Pending account switch: (account_name, db_path)
     pub pending_account_switch: Option<(String, PathBuf)>,
-    /// Pending background chat init (reply info, pinned, photos) after fast open
+    /// Pending background chat init (reply info, pinned) after fast open
     pub pending_chat_init: Option<ChatId>,
+    /// Receiver for background photo downloads (file_id, result path)
+    #[cfg(feature = "images")]
+    pub photo_download_rx:
+        Option<tokio::sync::mpsc::UnboundedReceiver<(i32, Result<String, String>)>>,
     // Voice playback
     /// Аудиопроигрыватель для голосовых сообщений (rodio)
     pub audio_player: Option<crate::audio::AudioPlayer>,
@@ -198,6 +202,8 @@ impl<T: TdClientTrait> App<T> {
             pending_account_switch: None,
             pending_chat_init: None,
             #[cfg(feature = "images")]
+            photo_download_rx: None,
+            #[cfg(feature = "images")]
             image_cache,
             #[cfg(feature = "images")]
             inline_image_renderer,

tests/account_switcher.rs

@@ -47,8 +47,15 @@ fn test_account_switcher_navigate_down() {
     let mut app = TestAppBuilder::new().build();
     app.open_account_switcher();
 
-    // Initially at 0, navigate down to "Add account" item
-    app.account_switcher_select_next();
+    let num_accounts = match &app.account_switcher {
+        Some(AccountSwitcherState::SelectAccount { accounts, .. }) => accounts.len(),
+        _ => panic!("Expected SelectAccount state"),
+    };
+
+    // Navigate down past all accounts to "Add account" item
+    for _ in 0..num_accounts {
+        app.account_switcher_select_next();
+    }
 
     match &app.account_switcher {
         Some(AccountSwitcherState::SelectAccount {
@@ -56,7 +63,7 @@ fn test_account_switcher_navigate_down() {
             accounts,
             ..
         }) => {
-            // Should be at index 1 (the "Add account" item, since default config has 1 account)
+            // Should be at the "Add account" item (index == accounts.len())
             assert_eq!(*selected_index, accounts.len());
         }
         _ => panic!("Expected SelectAccount state"),
@@ -116,8 +123,15 @@ fn test_confirm_add_account_transitions_to_add_state() {
     let mut app = TestAppBuilder::new().build();
     app.open_account_switcher();
 
-    // Navigate to "+ Add account"
-    app.account_switcher_select_next();
+    let num_accounts = match &app.account_switcher {
+        Some(AccountSwitcherState::SelectAccount { accounts, .. }) => accounts.len(),
+        _ => panic!("Expected SelectAccount state"),
+    };
+
+    // Navigate past all accounts to "+ Add account"
+    for _ in 0..num_accounts {
+        app.account_switcher_select_next();
+    }
 
     // Confirm should transition to AddAccount
     app.account_switcher_confirm();