refactor: implement trait-based DI for TdClient and fix stack overflow

Implement complete trait-based dependency injection pattern for TdClient
to enable testing with FakeTdClient mock. Fix critical stack overflow bugs
caused by infinite recursion in trait implementations.

Breaking Changes:
- App is now generic: App<T: TdClientTrait = TdClient>
- All UI and input handlers are generic over TdClientTrait
- TdClient methods now accessed through trait interface

New Files:
- src/tdlib/trait.rs: TdClientTrait definition with 40+ methods
- src/tdlib/client_impl.rs: TdClientTrait impl for TdClient
- tests/helpers/fake_tdclient_impl.rs: TdClientTrait impl for FakeTdClient

Critical Fixes:
- Fix stack overflow in send_message, edit_message, delete_messages
- Fix stack overflow in forward_messages, current_chat_messages
- Fix stack overflow in current_pinned_message
- All methods now call message_manager directly to avoid recursion

Testing:
- FakeTdClient supports configurable auth_state for auth screen tests
- Added pinned message support in FakeTdClient
- All 196+ tests passing (188 tests + 8 benchmarks)

Dependencies:
- Added async-trait = "0.1"

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

src/app/mod.rs

@@ -4,7 +4,7 @@ mod state;
 pub use chat_state::ChatState;
 pub use state::AppScreen;
 
-use crate::tdlib::{ChatInfo, TdClient};
+use crate::tdlib::{ChatInfo, TdClient, TdClientTrait};
 use crate::types::{ChatId, MessageId};
 use ratatui::widgets::ListState;
 
@@ -43,11 +43,11 @@ use ratatui::widgets::ListState;
 /// // Open a chat
 /// app.select_current_chat();
 /// ```
-pub struct App {
+pub struct App<T: TdClientTrait = TdClient> {
     // Core (config - readonly через getter)
     config: crate::config::Config,
     pub screen: AppScreen,
-    pub td_client: TdClient,
+    pub td_client: T,
     /// Состояние чата - type-safe state machine (новое!)
     pub chat_state: ChatState,
     // Auth state (используются часто в UI)
@@ -77,27 +77,27 @@ pub struct App {
     pub last_typing_sent: Option<std::time::Instant>,
 }
 
-impl App {
-    /// Creates a new App instance with the given configuration.
+impl<T: TdClientTrait> App<T> {
+    /// Creates a new App instance with the given configuration and client.
     ///
-    /// Initializes TDLib client, sets up empty chat list, and configures
-    /// the app to start on the Loading screen.
+    /// Sets up empty chat list and configures the app to start on the Loading screen.
     ///
     /// # Arguments
     ///
     /// * `config` - Application configuration loaded from config.toml
+    /// * `td_client` - TDLib client instance (real or fake for tests)
     ///
     /// # Returns
     ///
     /// A new `App` instance ready to start authentication.
-    pub fn new(config: crate::config::Config) -> App {
+    pub fn with_client(config: crate::config::Config, td_client: T) -> App<T> {
         let mut state = ListState::default();
         state.select(Some(0));
 
         App {
             config,
             screen: AppScreen::Loading,
-            td_client: TdClient::new(),
+            td_client,
             chat_state: ChatState::Normal,
             phone_input: String::new(),
             code_input: String::new(),
@@ -174,7 +174,7 @@ impl App {
         self.chat_state = ChatState::Normal;
         // Очищаем данные в TdClient
         self.td_client.set_current_chat_id(None);
-        self.td_client.current_chat_messages_mut().clear();
+        self.td_client.clear_current_chat_messages();
         self.td_client.set_typing_status(None);
         self.td_client.set_current_pinned_message(None);
     }
@@ -215,9 +215,9 @@ impl App {
     }
 
     /// Получить выбранное сообщение
-    pub fn get_selected_message(&self) -> Option<&crate::tdlib::MessageInfo> {
+    pub fn get_selected_message(&self) -> Option<crate::tdlib::MessageInfo> {
         self.chat_state.selected_message_index().and_then(|idx| {
-            self.td_client.current_chat_messages().get(idx)
+            self.td_client.current_chat_messages().get(idx).cloned()
         })
     }
 
@@ -397,12 +397,13 @@ impl App {
     }
 
     /// Получить сообщение, на которое отвечаем
-    pub fn get_replying_to_message(&self) -> Option<&crate::tdlib::MessageInfo> {
+    pub fn get_replying_to_message(&self) -> Option<crate::tdlib::MessageInfo> {
         self.chat_state.selected_message_id().and_then(|id| {
             self.td_client
                 .current_chat_messages()
                 .iter()
                 .find(|m| m.id() == id)
+                .cloned()
         })
     }
 
@@ -431,7 +432,7 @@ impl App {
     }
 
     /// Получить сообщение для пересылки
-    pub fn get_forwarding_message(&self) -> Option<&crate::tdlib::MessageInfo> {
+    pub fn get_forwarding_message(&self) -> Option<crate::tdlib::MessageInfo> {
         if !self.chat_state.is_forward() {
             return None;
         }
@@ -440,6 +441,7 @@ impl App {
                 .current_chat_messages()
                 .iter()
                 .find(|m| m.id() == id)
+                .cloned()
         })
     }
 
@@ -991,3 +993,22 @@ impl App {
         self.last_typing_sent = Some(std::time::Instant::now());
     }
 }
+
+// Convenience constructor for real TdClient (production use)
+impl App<TdClient> {
+    /// Creates a new App instance with the given configuration and a real TDLib client.
+    ///
+    /// This is a convenience method for production use that automatically creates
+    /// a new TdClient instance.
+    ///
+    /// # Arguments
+    ///
+    /// * `config` - Application configuration loaded from config.toml
+    ///
+    /// # Returns
+    ///
+    /// A new `App<TdClient>` instance ready to start authentication.
+    pub fn new(config: crate::config::Config) -> App<TdClient> {
+        App::with_client(config, TdClient::new())
+    }
+}