feat: add scroll to bottom button and auto-scroll on session load

src/pages/GamePage.css

@@ -225,6 +225,33 @@
   display: flex;
   flex-direction: column;
   overflow: hidden;
+  position: relative;
+}
+
+.scroll-to-bottom-btn {
+  position: absolute;
+  bottom: 5rem;
+  right: 1rem;
+  width: 40px;
+  height: 40px;
+  background: rgba(30, 30, 30, 0.9);
+  border: 1px solid rgba(255, 255, 255, 0.15);
+  border-radius: 50%;
+  color: #fff;
+  font-size: 1.25rem;
+  cursor: pointer;
+  display: flex;
+  align-items: center;
+  justify-content: center;
+  z-index: 5;
+  transition: all 0.2s;
+  backdrop-filter: blur(8px);
+  -webkit-backdrop-filter: blur(8px);
+}
+
+.scroll-to-bottom-btn:hover {
+  background: rgba(50, 50, 50, 0.95);
+  transform: scale(1.05);
 }
 
 .messages-container {
@@ -629,4 +656,12 @@
     right: 0;
     left: auto;
   }
+
+  .scroll-to-bottom-btn {
+    width: 36px;
+    height: 36px;
+    bottom: 4.5rem;
+    right: 0.75rem;
+    font-size: 1rem;
+  }
 }

src/pages/GamePage.tsx

@@ -60,8 +60,10 @@ export default function GamePage() {
   const [error, setError] = useState<string | null>(null);
   const [streamingContent, setStreamingContent] = useState("");
   const [showSessionMenu, setShowSessionMenu] = useState(false);
+  const [showScrollButton, setShowScrollButton] = useState(false);
   const abortControllerRef = useRef<AbortController | null>(null);
   const messagesEndRef = useRef<HTMLDivElement>(null);
+  const messagesContainerRef = useRef<HTMLDivElement>(null);
   const inputRef = useRef<HTMLTextAreaElement>(null);
 
   useEffect(() => {
@@ -159,10 +161,25 @@ export default function GamePage() {
     scrollToBottom();
   }, [session?.messages]);
 
+  // Scroll to bottom on session load
+  useEffect(() => {
+    if (session && !isInitialLoading) {
+      setTimeout(() => scrollToBottom(), 100);
+    }
+  }, [currentSessionId, isInitialLoading]);
+
   const scrollToBottom = () => {
     messagesEndRef.current?.scrollIntoView({ behavior: "smooth" });
   };
 
+  const handleScroll = () => {
+    const container = messagesContainerRef.current;
+    if (!container) return;
+    const { scrollTop, scrollHeight, clientHeight } = container;
+    const distanceFromBottom = scrollHeight - scrollTop - clientHeight;
+    setShowScrollButton(distanceFromBottom > 200);
+  };
+
   const startStory = async (
     storyData: Story,
     sessionData: GameSession,
@@ -528,7 +545,11 @@ export default function GamePage() {
       </header>
 
       <div className="game-content">
-        <div className="messages-container">
+        <div 
+          className="messages-container" 
+          ref={messagesContainerRef}
+          onScroll={handleScroll}
+        >
           {session?.messages.map((message) => (
             <div key={message.id} className={`message ${message.role}`}>
               <div className="message-content">
@@ -571,6 +592,12 @@ export default function GamePage() {
           <div ref={messagesEndRef} />
         </div>
 
+        {showScrollButton && (
+          <button className="scroll-to-bottom-btn" onClick={scrollToBottom}>
+            ↓
+          </button>
+        )}
+
         {/* RPG кнопки скрыты — раскомментировать при необходимости
         <div className="quick-actions">
           <button onClick={() => handleQuickAction("Осмотреться вокруг")}>