feat(server,app): redesign git/GitHub refresh architecture with server authority

Centralizes refresh orchestration in WorkspaceGitService and GitHubService:
server coalesces, deduplicates, and throttles git/GitHub reads; clients peek
snapshots (cold reads fall through to a one-shot fetch) and never drive
refreshes. Introduces a two-TTL model (consumer vs internal), force-emit
bypass so fingerprint-matched refreshes still propagate, notifyGitMutation
wiring at ~13 action handlers, adaptive GitHub polling based on check state,
and checkout_status_update / prStatus push-to-cache wire messages. Fixes the
stale diff-stat bug and the inverted base-branch diff direction, and flips
next-action affordances promptly after commit / PR merge.

packages/app/src/hooks/use-checkout-pr-status-query.ts

@@ -1,10 +1,8 @@
-import { useQuery } from "@tanstack/react-query";
+import { useQuery, useQueryClient } from "@tanstack/react-query";
+import { useEffect } from "react";
 import { useHostRuntimeClient, useHostRuntimeIsConnected } from "@/runtime/host-runtime";
 import type { CheckoutPrStatusResponse } from "@server/shared/messages";
 
-const CHECKOUT_PR_STATUS_STALE_TIME = 20_000;
-const WORKSPACE_PR_HINT_REFETCH_INTERVAL = 60_000;
-
 export function checkoutPrStatusQueryKey(serverId: string, cwd: string) {
   return ["checkoutPrStatus", serverId, cwd] as const;
 }
@@ -16,6 +14,7 @@ interface UseCheckoutPrStatusQueryOptions {
 }
 
 export type CheckoutPrStatusPayload = CheckoutPrStatusResponse["payload"];
+
 export interface PrHint {
   url: string;
   number: number;
@@ -71,9 +70,24 @@ export function useCheckoutPrStatusQuery({
   cwd,
   enabled = true,
 }: UseCheckoutPrStatusQueryOptions) {
+  const queryClient = useQueryClient();
   const client = useHostRuntimeClient(serverId);
   const isConnected = useHostRuntimeIsConnected(serverId);
 
+  useEffect(() => {
+    if (!client || !isConnected || !cwd) {
+      return;
+    }
+
+    return client.on("checkout_status_update", (message) => {
+      const prStatus = message.payload.prStatus;
+      if (!prStatus || prStatus.cwd !== cwd) {
+        return;
+      }
+      queryClient.setQueryData(checkoutPrStatusQueryKey(serverId, cwd), prStatus);
+    });
+  }, [client, isConnected, cwd, queryClient, serverId]);
+
   const query = useQuery({
     queryKey: checkoutPrStatusQueryKey(serverId, cwd),
     queryFn: async () => {
@@ -83,8 +97,10 @@ export function useCheckoutPrStatusQuery({
       return await client.checkoutPrStatus(cwd);
     },
     enabled: !!client && isConnected && !!cwd && enabled,
-    staleTime: CHECKOUT_PR_STATUS_STALE_TIME,
-    refetchInterval: 15_000,
+    staleTime: Infinity,
+    refetchOnMount: false,
+    refetchOnReconnect: false,
+    refetchOnWindowFocus: false,
   });
 
   return {
@@ -95,7 +111,6 @@ export function useCheckoutPrStatusQuery({
     isFetching: query.isFetching,
     isError: query.isError,
     error: query.error,
-    refresh: query.refetch,
   };
 }
 
@@ -104,9 +119,24 @@ export function useWorkspacePrHint({
   cwd,
   enabled = true,
 }: UseCheckoutPrStatusQueryOptions): PrHint | null {
+  const queryClient = useQueryClient();
   const client = useHostRuntimeClient(serverId);
   const isConnected = useHostRuntimeIsConnected(serverId);
 
+  useEffect(() => {
+    if (!client || !isConnected || !cwd) {
+      return;
+    }
+
+    return client.on("checkout_status_update", (message) => {
+      const prStatus = message.payload.prStatus;
+      if (!prStatus || prStatus.cwd !== cwd) {
+        return;
+      }
+      queryClient.setQueryData(checkoutPrStatusQueryKey(serverId, cwd), prStatus);
+    });
+  }, [client, isConnected, cwd, queryClient, serverId]);
+
   const query = useQuery<CheckoutPrStatusPayload, Error, PrHint | null>({
     queryKey: checkoutPrStatusQueryKey(serverId, cwd),
     queryFn: async () => {
@@ -116,8 +146,10 @@ export function useWorkspacePrHint({
       return await client.checkoutPrStatus(cwd);
     },
     enabled: !!client && isConnected && !!cwd && enabled,
-    staleTime: CHECKOUT_PR_STATUS_STALE_TIME,
-    refetchInterval: WORKSPACE_PR_HINT_REFETCH_INTERVAL,
+    staleTime: Infinity,
+    refetchOnMount: false,
+    refetchOnReconnect: false,
+    refetchOnWindowFocus: false,
     select: selectWorkspacePrHint,
   });