feat: separate system task token usage and add usage refresh

Add a System tasks tab to run history that splits background usage (supervisor, auto-supervision, magic notes, knowledge base, delegation) from conversation usage, with a manual refresh button and automatic refresh when usage is recorded. Record previously dropped usage from supervisor reviews, image regeneration, knowledge graph extraction, and remote embeddings.

src/preload/index.ts

@@ -1283,7 +1283,13 @@ const desktopApi: DesktopApi = {
     getTokenSummary: () =>
       ipcRenderer.invoke(
         ipcChannels.tokenUsageSummary
-      ) as Promise<TokenUsageSummary>
+      ) as Promise<TokenUsageSummary>,
+    onChanged: (listener) => {
+      const handler = (): void => listener()
+      ipcRenderer.on(ipcChannels.tokenUsageChanged, handler)
+      return () =>
+        ipcRenderer.removeListener(ipcChannels.tokenUsageChanged, handler)
+    }
   },
   artifacts: {
     list: (projectId?: string) =>