fix: stop conversation draft leaking into home chat input

__tests__/hooks/use-draft-persistence.test.tsx

@@ -15,6 +15,16 @@ vi.mock("#/components/features/chat/utils/chat-input.utils", () => ({
   getTextContent: vi.fn((el: HTMLDivElement | null) => el?.textContent || ""),
 }));
 
+const mockSetMessageToSend = vi.fn();
+
+vi.mock("#/stores/conversation-store", () => ({
+  useConversationStore: {
+    getState: () => ({
+      setMessageToSend: mockSetMessageToSend,
+    }),
+  },
+}));
+
 describe("useDraftPersistence", () => {
   let mockSetDraftMessage: (message: string | null) => void;
 
@@ -28,6 +38,7 @@ describe("useDraftPersistence", () => {
 
   beforeEach(() => {
     vi.clearAllMocks();
+    mockSetMessageToSend.mockClear();
     vi.useFakeTimers();
     localStorage.clear();
 
@@ -69,6 +80,39 @@ describe("useDraftPersistence", () => {
     vi.clearAllMocks();
   });
 
+  describe("home / zero state (no conversationId)", () => {
+    it("clears the input and session messageToSend instead of restoring a draft", () => {
+      const staleDraft = "Draft that must not appear on home";
+      const chatInputRef = createMockChatInputRef(staleDraft);
+
+      renderHook(() =>
+        useDraftPersistence(undefined, chatInputRef),
+      );
+
+      expect(chatInputRef.current?.textContent).toBe("");
+      expect(mockSetMessageToSend).toHaveBeenCalledWith("");
+      expect(conversationLocalStorage.getConversationState).not.toHaveBeenCalled();
+    });
+
+    it("saveDraft is a no-op without a conversationId", () => {
+      const chatInputRef = createMockChatInputRef("typed on home");
+
+      const { result } = renderHook(() =>
+        useDraftPersistence(undefined, chatInputRef),
+      );
+
+      act(() => {
+        result.current.saveDraft();
+      });
+
+      act(() => {
+        vi.advanceTimersByTime(500);
+      });
+
+      expect(mockSetDraftMessage).not.toHaveBeenCalled();
+    });
+  });
+
   describe("draft restoration on mount", () => {
     it("restores draft from localStorage when mounting with existing draft", () => {
       // Arrange
@@ -504,6 +548,8 @@ describe("useDraftPersistence", () => {
       // Act - normal conversation switch (not task-to-real)
       rerender({ conversationId: "conv-B" });
 
+      expect(mockSetMessageToSend).toHaveBeenCalledWith("");
+
       // Assert - should not use setConversationState directly
       // (the normal path uses setDraftMessage from the hook)
       expect(conversationLocalStorage.setConversationState).not.toHaveBeenCalled();

src/hooks/chat/use-chat-input-logic.ts

@@ -31,6 +31,8 @@ export const useChatInputLogic = () => {
     chatInputRef,
   );
 
+  const messageToSendForResize = conversationId ? messageToSend : null;
+
   // Save current input value when drawer state changes
   useEffect(() => {
     if (chatInputRef.current) {
@@ -59,7 +61,7 @@ export const useChatInputLogic = () => {
 
   return {
     chatInputRef,
-    messageToSend,
+    messageToSend: messageToSendForResize,
     checkIsContentEmpty,
     clearEmptyContentHandler,
     getCurrentMessage,

src/hooks/chat/use-draft-persistence.ts

@@ -5,6 +5,7 @@
   setConversationState,
 } from "#/utils/conversation-local-storage";
 import { getTextContent } from "#/components/features/chat/utils/chat-input.utils";
+import { useConversationStore } from "#/stores/conversation-store";
 
 /**
  * Check if a conversation ID is a temporary task ID.
@@ -41,6 +42,27 @@
   // Track if this is the first mount to handle initial cleanup
   const isFirstMountRef = useRef(true);
 
+  useEffect(() => {
+    if (conversationId) {
+      return;
+    }
+
+    useConversationStore.getState().setMessageToSend("");
+
+    if (saveTimeoutRef.current) {
+      clearTimeout(saveTimeoutRef.current);
+      saveTimeoutRef.current = null;
+    }
+
+    const element = chatInputRef.current;
+    if (element) {
+      element.textContent = "";
+    }
+
+    hasRestoredRef.current = false;
+    setIsRestored(false);
+  }, [conversationId, chatInputRef]);
+
   // IMPORTANT: This effect must run FIRST when conversation changes.
   // It handles three concerns:
   // 1. Cleanup: Cancel pending saves from previous conversation
@@ -62,6 +84,8 @@
       saveTimeoutRef.current = null;
     }
 
+     useConversationStore.getState().setMessageToSend("");
+
     const element = chatInputRef.current;
 
     // --- 2. Handle task-to-real ID transition (preserve draft during initialization) ---

src/hooks/use-auto-resize.ts

@@ -325,11 +325,9 @@
       manualHeightRef.current = finalHeight;
     }
   };
-
-  // Update content and resize when value prop changes
-  useEffect(() => {
+useEffect(() => {
     const element = elementRef.current;
-    if (element && value !== undefined) {
+    if (element && value !== undefined && value.text.length > 0) {
       element.textContent = value.text;
       smartResize();
     }