feat(characters): support character-scoped conversations

src/app/chat/chat-screen.tsx

@@ -52,6 +52,7 @@ export function ChatScreen() {
   const authState = useAuthState();
   const authDispatch = useAuthDispatch();
   useSplashLatestMessageSync({
+    characterId: state.characterId,
     historyLoaded: state.historyLoaded,
     loginStatus: authState.loginStatus,
     messages: state.historyMessages,
@@ -182,6 +183,7 @@ export function ChatScreen() {
           />
 
           <ChatArea
+            characterId={state.characterId}
             messages={visibleMessages}
             isReplyingAI={state.isReplyingAI}
             scrollToBottomSignal={state.outgoingMessageRevision}
@@ -220,6 +222,7 @@ export function ChatScreen() {
 
         {selectedImageMessage?.imageUrl ? (
           <FullscreenImageViewer
+            characterId={state.characterId}
             messageId={selectedImageMessage.id}
             imageUrl={selectedImageMessage.imageUrl}
             imagePaywalled={selectedImageMessage.imagePaywalled === true}

src/app/chat/components/chat-area.tsx

@@ -24,6 +24,7 @@ import {
 import { LoaderCircle } from "lucide-react";
 
 import type { UiMessage } from "@/data/dto/chat";
+import { DEFAULT_CHARACTER_ID } from "@/data/constants/character";
 import { usePullToRefresh } from "@/hooks/use-pull-to-refresh";
 
 import {
@@ -45,6 +46,7 @@ const ReplyingAnimation = lazy(() =>
 );
 
 export interface ChatAreaProps {
+  characterId?: string;
   messages: readonly UiMessage[];
   isReplyingAI: boolean;
   scrollToBottomSignal?: number;
@@ -61,6 +63,7 @@ export interface ChatAreaProps {
 }
 
 export function ChatArea({
+  characterId = DEFAULT_CHARACTER_ID,
   messages,
   isReplyingAI,
   scrollToBottomSignal = 0,
@@ -235,6 +238,7 @@ export function ChatArea({
         <AiDisclosureBanner />
 
         {renderMessagesWithDateHeaders(
+          characterId,
           messages,
           getMessageKey,
           isUnlockingMessage,
@@ -270,6 +274,7 @@ function isNearBottom(scrollNode: HTMLElement): boolean {
 
 /** 渲染消息列表（按日期分组插入分隔条） */
 function renderMessagesWithDateHeaders(
+  characterId: string,
   messages: readonly UiMessage[],
   getMessageKey: ChatMessageKeyResolver,
   isUnlockingMessage?: boolean,
@@ -284,6 +289,7 @@ function renderMessagesWithDateHeaders(
       <DateHeader key={item.key} date={item.date} />
     ) : (
       <MessageBubble
+        characterId={characterId}
         key={item.key}
         messageId={item.message.id}
         content={item.message.content}

src/app/chat/components/chat-media-image.tsx

@@ -12,6 +12,7 @@ import {
 import { useCachedChatMediaUrl } from "@/lib/chat/use_cached_chat_media_url";
 
 export interface ChatMediaImageProps {
+  characterId: string;
   messageId?: string;
   remoteUrl: string;
   alt?: string;
@@ -28,6 +29,7 @@ export interface ChatMediaImageProps {
 }
 
 export function ChatMediaImage({
+  characterId,
   messageId,
   remoteUrl,
   alt = "",
@@ -45,6 +47,7 @@ export function ChatMediaImage({
   const [errorSrc, setErrorSrc] = useState<string | null>(null);
   const { mediaUrl, isUsingCachedMedia, reportMediaError } =
     useCachedChatMediaUrl({
+      characterId,
       messageId,
       remoteUrl,
       kind: "image",

src/app/chat/components/fullscreen-image-viewer.tsx

@@ -18,6 +18,7 @@ import { ChatMediaImage } from "./chat-media-image";
 import styles from "./fullscreen-image-viewer.module.css";
 
 export interface FullscreenImageViewerProps {
+  characterId: string;
   messageId?: string;
   imageUrl: string;
   imagePaywalled?: boolean;
@@ -27,6 +28,7 @@ export interface FullscreenImageViewerProps {
 }
 
 export function FullscreenImageViewer({
+  characterId,
   messageId,
   imageUrl,
   imagePaywalled = false,
@@ -51,6 +53,7 @@ export function FullscreenImageViewer({
         aria-label="Locked fullscreen image"
       >
         <ChatMediaImage
+          characterId={characterId}
           messageId={messageId}
           remoteUrl={imageUrl}
           className={styles.paywallImage}
@@ -100,6 +103,7 @@ export function FullscreenImageViewer({
         variant="unstyled"
       />
       <ChatMediaImage
+        characterId={characterId}
         messageId={messageId}
         remoteUrl={imageUrl}
         className={styles.viewerImage}

src/app/chat/components/image-bubble.tsx

@@ -9,8 +9,10 @@
  */
 
 import { ChatMediaImage } from "./chat-media-image";
+import { DEFAULT_CHARACTER_ID } from "@/data/constants/character";
 
 export interface ImageBubbleProps {
+  characterId?: string;
   messageId?: string;
   imageUrl: string; // base64 data URI 或 URL
   imagePaywalled?: boolean;
@@ -18,6 +20,7 @@ export interface ImageBubbleProps {
 }
 
 export function ImageBubble({
+  characterId = DEFAULT_CHARACTER_ID,
   messageId,
   imageUrl,
   imagePaywalled = false,
@@ -52,6 +55,7 @@ export function ImageBubble({
       aria-label={canOpen ? "Open image in fullscreen" : undefined}
     >
       <ChatMediaImage
+        characterId={characterId}
         messageId={messageId}
         remoteUrl={imageUrl}
         className={imageClassName}

src/app/chat/components/message-bubble.tsx

@@ -15,6 +15,7 @@ import { MessageContent } from "./message-content";
 import styles from "./chat-area.module.css";
 
 export interface MessageBubbleProps {
+  characterId: string;
   messageId?: string;
   content: string;
   imageUrl?: string | null;
@@ -33,6 +34,7 @@ export interface MessageBubbleProps {
 }
 
 export function MessageBubble({
+  characterId,
   messageId,
   content,
   imageUrl,
@@ -61,6 +63,7 @@ export function MessageBubble({
         <MessageAvatar isFromAI={true} />
         <div className={styles.bubbleInlineSpacer} aria-hidden="true" />
         <MessageContent
+          characterId={characterId}
           content={content}
           imageUrl={imageUrl}
           imagePaywalled={imagePaywalled}
@@ -90,6 +93,7 @@ export function MessageBubble({
     >
       <div className={styles.bubbleAvatarSpacer} aria-hidden="true" />
       <MessageContent
+        characterId={characterId}
         content={content}
         imageUrl={imageUrl}
         imagePaywalled={imagePaywalled}

src/app/chat/components/message-content.tsx

@@ -7,6 +7,7 @@ import { VoiceBubble } from "./voice-bubble";
 import styles from "./chat-area.module.css";
 
 export interface MessageContentProps {
+  characterId: string;
   content: string;
   imageUrl?: string | null;
   imagePaywalled?: boolean;
@@ -27,6 +28,7 @@ export interface MessageContentProps {
 const IMAGE_PLACEHOLDER = "[图片]";
 
 export function MessageContent({
+  characterId,
   content,
   imageUrl,
   imagePaywalled,
@@ -90,6 +92,7 @@ export function MessageContent({
         <>
           {hasImage && imageUrl && (
             <ImageBubble
+              characterId={characterId}
               messageId={messageId}
               imageUrl={imageUrl}
               imagePaywalled={imagePaywalled}
@@ -98,6 +101,7 @@ export function MessageContent({
           )}
           {shouldRenderVoiceMessage ? (
             <VoiceBubble
+              characterId={characterId}
               messageId={messageId}
               audioUrl={audioUrl}
               isFromAI={isFromAI}

src/app/chat/components/voice-bubble.tsx

@@ -7,6 +7,7 @@ import { useCachedChatMediaUrl } from "@/lib/chat/use_cached_chat_media_url";
 import styles from "./voice-bubble.module.css";
 
 export interface VoiceBubbleProps {
+  characterId: string;
   messageId?: string;
   audioUrl?: string | null;
   isFromAI: boolean;
@@ -17,6 +18,7 @@ export interface VoiceBubbleProps {
 }
 
 export function VoiceBubble({
+  characterId,
   messageId,
   audioUrl,
   isFromAI,
@@ -31,6 +33,7 @@ export function VoiceBubble({
   const hasAudio = audioUrl != null && audioUrl.length > 0;
   const { mediaUrl, isUsingCachedMedia, reportMediaError } =
     useCachedChatMediaUrl({
+      characterId,
       messageId,
       remoteUrl: audioUrl,
       kind: "audio",

src/app/chat/hooks/use-splash-latest-message-sync.ts

@@ -9,12 +9,14 @@ import { getLatestSplashMessagePreview } from "@/lib/chat/splash_latest_message_
 import { useSplashLatestMessageCache } from "@/providers/splash-latest-message-provider";
 
 export interface UseSplashLatestMessageSyncInput {
+  characterId: string;
   historyLoaded: boolean;
   loginStatus: LoginStatus;
   messages: readonly UiMessage[];
 }
 
 export function useSplashLatestMessageSync({
+  characterId,
   historyLoaded,
   loginStatus,
   messages,
@@ -26,7 +28,7 @@ export function useSplashLatestMessageSync({
   useEffect(() => {
     hasObservedInitialSnapshotRef.current = false;
     identityPromiseRef.current = null;
-  }, [loginStatus]);
+  }, [characterId, loginStatus]);
 
   useEffect(() => {
     if (!historyLoaded) return;
@@ -39,7 +41,8 @@ export function useSplashLatestMessageSync({
     const preview = getLatestSplashMessagePreview(messages);
     let cancelled = false;
 
-    identityPromiseRef.current ??= resolveSplashLatestMessageCacheIdentity();
+    identityPromiseRef.current ??=
+      resolveSplashLatestMessageCacheIdentity(characterId);
     void identityPromiseRef.current.then((identity) => {
       if (!cancelled && identity) {
         cache.set(identity, preview);
@@ -49,5 +52,5 @@ export function useSplashLatestMessageSync({
     return () => {
       cancelled = true;
     };
-  }, [cache, historyLoaded, messages]);
+  }, [cache, characterId, historyLoaded, messages]);
 }