refactor(structure): announce presence throttled

When we introduced presence in the PortableTextInput, we risk calling the presence updates very often.
There should be no reason for not doing this throttled, as long as we have leading true.

packages/sanity/src/structure/panes/document/DocumentPaneProvider.tsx

@@ -8,7 +8,7 @@ import {
 } from '@sanity/types'
 import {useToast} from '@sanity/ui'
 import {fromString as pathFromString, resolveKeyedPath} from '@sanity/util/paths'
-import {omit} from 'lodash'
+import {omit, throttle} from 'lodash'
 import {memo, useCallback, useEffect, useMemo, useRef, useState} from 'react'
 import deepEquals from 'react-fast-compare'
 import {
@@ -548,15 +548,8 @@ export const DocumentPaneProvider = memo((props: DocumentPaneProviderProps) => {
     [formStateRef],
   )
 
-  const handleFocus = useCallback(
+  const updatePresence = useCallback(
     (nextFocusPath: Path, payload?: OnPathFocusPayload) => {
-      setFocusPath(nextFocusPath)
-      if (!deepEquals(focusPathRef.current, nextFocusPath)) {
-        setOpenPath(nextFocusPath.slice(0, -1))
-        focusPathRef.current = nextFocusPath
-        onFocusPath?.(nextFocusPath)
-      }
-
       presenceStore.setLocation([
         {
           type: 'document',
@@ -567,7 +560,25 @@ export const DocumentPaneProvider = memo((props: DocumentPaneProviderProps) => {
         },
       ])
     },
-    [documentId, onFocusPath, presenceStore, setOpenPath],
+    [documentId, presenceStore],
+  )
+
+  const updatePresenceThrottled = useMemo(
+    () => throttle(updatePresence, 1000, {leading: true, trailing: true}),
+    [updatePresence],
+  )
+
+  const handleFocus = useCallback(
+    (nextFocusPath: Path, payload?: OnPathFocusPayload) => {
+      setFocusPath(nextFocusPath)
+      if (!deepEquals(focusPathRef.current, nextFocusPath)) {
+        setOpenPath(nextFocusPath.slice(0, -1))
+        focusPathRef.current = nextFocusPath
+        onFocusPath?.(nextFocusPath)
+      }
+      updatePresenceThrottled(nextFocusPath, payload)
+    },
+    [onFocusPath, setOpenPath, updatePresenceThrottled],
   )
 
   const documentPane: DocumentPaneContextValue = useMemo(