fix(billing): skip the activity refresh on first balance hydration

UsageLogsTable now loads itself, so refreshing again when the balance
first resolves fetched activity twice per panel open.

Author: dante01yoon

src/components/dialog/content/setting/CreditsPanel.test.ts

@@ -103,13 +103,15 @@ describe('CreditsPanel', () => {
     expect(billingMocks.manageSubscription).toHaveBeenCalledOnce()
   })
 
-  it('refreshes activity when the rendered balance changes', async () => {
+  it('refreshes activity on a balance change but not on first hydration', async () => {
     renderComponent()
-    expect(refreshActivity).not.toHaveBeenCalled()
 
     billingMocks.balance.value = makeBalance(5000)
     await nextTick()
+    expect(refreshActivity).not.toHaveBeenCalled()
 
+    billingMocks.balance.value = makeBalance(9000)
+    await nextTick()
     expect(refreshActivity).toHaveBeenCalledOnce()
   })
 })

src/components/dialog/content/setting/CreditsPanel.vue

@@ -55,7 +55,8 @@ const telemetry = useTelemetry()
 
 const usageLogsTableRef = ref<InstanceType<typeof UsageLogsTable> | null>(null)
 
-watch(balance, () => {
+watch(balance, (next, previous) => {
+  if (!next || !previous) return
   void usageLogsTableRef.value?.refresh()
 })