feat: implement Phase 11 — inline photo viewing with ratatui-image

Add feature-gated (`images`) inline photo support:
- New types: MediaInfo, PhotoInfo, PhotoDownloadState, ImagesConfig
- Media module: ImageCache (LRU filesystem cache), ImageRenderer (terminal protocol detection)
- Photo metadata extraction from TDLib MessagePhoto with download_file() API
- ViewImage command (v/м) to toggle photo expand/collapse in message selection
- Two-pass UI rendering: placeholder lines in message bubbles + StatefulImage overlay
- Collapse all expanded photos on Esc (exit selection mode)

Dependencies: ratatui-image 8.1, image 0.25 (optional, behind `images` feature flag)

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

src/input/handlers/chat.rs

@@ -68,6 +68,10 @@ pub async fn handle_message_selection<T: TdClientTrait>(app: &mut App<T>, _key:
                 }
             }
         }
+        #[cfg(feature = "images")]
+        Some(crate::config::Command::ViewImage) => {
+            handle_view_image(app).await;
+        }
         Some(crate::config::Command::ReactMessage) => {
             let Some(msg) = app.get_selected_message() else {
                 return;
@@ -461,4 +465,168 @@ pub async fn handle_open_chat_keyboard_input<T: TdClientTrait>(app: &mut App<T>,
         }
         _ => {}
     }
+}
+
+/// Обработка команды ViewImage — раскрыть/свернуть превью фото
+#[cfg(feature = "images")]
+async fn handle_view_image<T: TdClientTrait>(app: &mut App<T>) {
+    use crate::tdlib::PhotoDownloadState;
+
+    if !app.config().images.show_images {
+        return;
+    }
+
+    let Some(msg) = app.get_selected_message() else {
+        return;
+    };
+
+    if !msg.has_photo() {
+        app.status_message = Some("Сообщение не содержит фото".to_string());
+        return;
+    }
+
+    let photo = msg.photo_info().unwrap();
+    let file_id = photo.file_id;
+    let msg_id = msg.id();
+
+    match &photo.download_state {
+        PhotoDownloadState::Downloaded(_) if photo.expanded => {
+            // Свернуть
+            collapse_photo(app, msg_id);
+        }
+        PhotoDownloadState::Downloaded(path) => {
+            // Раскрыть (файл уже скачан)
+            let path = path.clone();
+            expand_photo(app, msg_id, &path);
+        }
+        PhotoDownloadState::NotDownloaded => {
+            // Проверяем кэш, затем скачиваем
+            download_and_expand(app, msg_id, file_id).await;
+        }
+        PhotoDownloadState::Downloading => {
+            // Скачивание уже идёт, игнорируем
+        }
+        PhotoDownloadState::Error(_) => {
+            // Попробуем перескачать
+            download_and_expand(app, msg_id, file_id).await;
+        }
+    }
+}
+
+#[cfg(feature = "images")]
+fn collapse_photo<T: TdClientTrait>(app: &mut App<T>, msg_id: crate::types::MessageId) {
+    // Свернуть изображение
+    let messages = app.td_client.current_chat_messages_mut();
+    if let Some(msg) = messages.iter_mut().find(|m| m.id() == msg_id) {
+        if let Some(photo) = msg.photo_info_mut() {
+            photo.expanded = false;
+        }
+    }
+    // Удаляем протокол из рендерера
+    #[cfg(feature = "images")]
+    if let Some(renderer) = &mut app.image_renderer {
+        renderer.remove(&msg_id);
+    }
+    app.needs_redraw = true;
+}
+
+#[cfg(feature = "images")]
+fn expand_photo<T: TdClientTrait>(app: &mut App<T>, msg_id: crate::types::MessageId, path: &str) {
+    // Загружаем изображение в рендерер
+    #[cfg(feature = "images")]
+    if let Some(renderer) = &mut app.image_renderer {
+        if let Err(e) = renderer.load_image(msg_id, path) {
+            app.error_message = Some(format!("Ошибка загрузки изображения: {}", e));
+            return;
+        }
+    }
+    // Ставим expanded = true
+    let messages = app.td_client.current_chat_messages_mut();
+    if let Some(msg) = messages.iter_mut().find(|m| m.id() == msg_id) {
+        if let Some(photo) = msg.photo_info_mut() {
+            photo.expanded = true;
+        }
+    }
+    app.needs_redraw = true;
+}
+
+#[cfg(feature = "images")]
+async fn download_and_expand<T: TdClientTrait>(app: &mut App<T>, msg_id: crate::types::MessageId, file_id: i32) {
+    use crate::tdlib::PhotoDownloadState;
+
+    // Проверяем кэш
+    #[cfg(feature = "images")]
+    if let Some(ref cache) = app.image_cache {
+        if let Some(cached_path) = cache.get_cached(file_id) {
+            let path_str = cached_path.to_string_lossy().to_string();
+            // Обновляем download_state
+            let messages = app.td_client.current_chat_messages_mut();
+            if let Some(msg) = messages.iter_mut().find(|m| m.id() == msg_id) {
+                if let Some(photo) = msg.photo_info_mut() {
+                    photo.download_state = PhotoDownloadState::Downloaded(path_str.clone());
+                }
+            }
+            expand_photo(app, msg_id, &path_str);
+            return;
+        }
+    }
+
+    // Ставим состояние Downloading
+    {
+        let messages = app.td_client.current_chat_messages_mut();
+        if let Some(msg) = messages.iter_mut().find(|m| m.id() == msg_id) {
+            if let Some(photo) = msg.photo_info_mut() {
+                photo.download_state = PhotoDownloadState::Downloading;
+            }
+        }
+    }
+    app.status_message = Some("Загрузка фото...".to_string());
+    app.needs_redraw = true;
+
+    // Скачиваем
+    match crate::utils::with_timeout_msg(
+        Duration::from_secs(crate::constants::FILE_DOWNLOAD_TIMEOUT_SECS),
+        app.td_client.download_file(file_id),
+        "Таймаут скачивания фото",
+    )
+    .await
+    {
+        Ok(path) => {
+            // Кэшируем
+            #[cfg(feature = "images")]
+            let cache_path = if let Some(ref cache) = app.image_cache {
+                cache.cache_file(file_id, &path).ok()
+            } else {
+                None
+            };
+            #[cfg(not(feature = "images"))]
+            let cache_path: Option<std::path::PathBuf> = None;
+
+            let final_path = cache_path
+                .map(|p| p.to_string_lossy().to_string())
+                .unwrap_or(path);
+
+            // Обновляем download_state
+            let messages = app.td_client.current_chat_messages_mut();
+            if let Some(msg) = messages.iter_mut().find(|m| m.id() == msg_id) {
+                if let Some(photo) = msg.photo_info_mut() {
+                    photo.download_state = PhotoDownloadState::Downloaded(final_path.clone());
+                }
+            }
+            app.status_message = None;
+            expand_photo(app, msg_id, &final_path);
+        }
+        Err(e) => {
+            // Ставим Error
+            let messages = app.td_client.current_chat_messages_mut();
+            if let Some(msg) = messages.iter_mut().find(|m| m.id() == msg_id) {
+                if let Some(photo) = msg.photo_info_mut() {
+                    photo.download_state = PhotoDownloadState::Error(e.clone());
+                }
+            }
+            app.error_message = Some(e);
+            app.status_message = None;
+            app.needs_redraw = true;
+        }
+    }
 }

src/input/main_input.rs

@@ -40,6 +40,18 @@ use crossterm::event::KeyEvent;
 async fn handle_escape_key<T: TdClientTrait>(app: &mut App<T>) {
     // Early return для режима выбора сообщения
     if app.is_selecting_message() {
+        // Свернуть все раскрытые фото (но сохранить Downloaded paths для re-expansion)
+        #[cfg(feature = "images")]
+        {
+            for msg in app.td_client.current_chat_messages_mut() {
+                if let Some(photo) = msg.photo_info_mut() {
+                    photo.expanded = false;
+                }
+            }
+            if let Some(renderer) = &mut app.image_renderer {
+                renderer.clear();
+            }
+        }
         app.chat_state = crate::app::ChatState::Normal;
         return;
     }