feat: enhance theme management and image caching functionality

src/stores/chat.ts

@@ -9,6 +9,7 @@ import { extractText, isToolOnlyMessage, isToolResultRole, isInternalMessage } f
 import { hostApiFetch } from '@lib/host-api'
 import { gatewayRpc, onGatewayEvent } from '@lib/gateway-client'
 import { useProviderStore } from '@stores/providers'
+import { IPC_EVENTS, CONFIG_KEYS } from '@lib/constants'
 
 // ── Constants ───────────────────────────────────────────────────
 const DEFAULT_SESSION_KEY = 'agent:main:main'
@@ -32,7 +33,6 @@ let _lastLoadSessionsAt = 0
 const _historyLoadInFlight = new Map<string, Promise<void>>()
 const _lastHistoryLoadAtBySession = new Map<string, number>()
 const _chatEventDedupe = new Map<string, number>()
-const IMAGE_CACHE_KEY = 'zn-ai:image-cache'
 const IMAGE_CACHE_MAX = 100
 
 // ── Helpers: Timers ─────────────────────────────────────────────
@@ -90,29 +90,35 @@ function isDuplicateChatEvent(eventState: string, event: Record<string, unknown>
 }
 
 // ── Helpers: Image Cache ────────────────────────────────────────
-function loadImageCache(): Map<string, AttachedFileMeta> {
+let _imageCache: Map<string, AttachedFileMeta> = new Map()
+let _imageCacheInitialized = false
+
+async function initImageCache(): Promise<void> {
+  if (_imageCacheInitialized) return
+  _imageCache = await loadImageCache()
+  _imageCacheInitialized = true
+}
+
+async function loadImageCache(): Promise<Map<string, AttachedFileMeta>> {
   try {
-    const raw = localStorage.getItem(IMAGE_CACHE_KEY)
-    if (raw) {
-      const entries = JSON.parse(raw) as Array<[string, AttachedFileMeta]>
-      return new Map(entries)
+    const raw = await window.api.invoke(IPC_EVENTS.GET_CONFIG, CONFIG_KEYS.IMAGE_CACHE)
+    if (Array.isArray(raw)) {
+      return new Map(raw as Array<[string, AttachedFileMeta]>)
     }
   } catch { /* ignore */ }
   return new Map()
 }
 
-function saveImageCache(cache: Map<string, AttachedFileMeta>): void {
+async function saveImageCache(cache: Map<string, AttachedFileMeta>): Promise<void> {
   try {
     const entries = Array.from(cache.entries())
     const trimmed = entries.length > IMAGE_CACHE_MAX
       ? entries.slice(entries.length - IMAGE_CACHE_MAX)
       : entries
-    localStorage.setItem(IMAGE_CACHE_KEY, JSON.stringify(trimmed))
+    await window.api.invoke(IPC_EVENTS.SET_CONFIG, CONFIG_KEYS.IMAGE_CACHE, trimmed)
   } catch { /* ignore */ }
 }
 
-const _imageCache = loadImageCache()
-
 // ── Helpers: Timestamp ──────────────────────────────────────────
 function toMs(ts: number): number {
   return ts < 1e12 ? ts * 1000 : ts
@@ -918,6 +924,7 @@ export const useChatStore = defineStore('chat', {
       try {
         // Cache image attachments
         if (attachments && attachments.length > 0) {
+          await initImageCache()
           for (const a of attachments) {
             _imageCache.set(a.stagedPath, {
               fileName: a.fileName,
@@ -926,7 +933,7 @@ export const useChatStore = defineStore('chat', {
               preview: a.preview,
             })
           }
-          saveImageCache(_imageCache)
+          await saveImageCache(_imageCache)
         }
 
         let messageContent = trimmed