[web/document-updater] display preview for accepted/rejected tracked changes (#36240)

* [web] add preview payload to track-change notification types

* [doc-updater] pass accepted/rejected change data through to web for previews

* [web] snapshot change preview onto accepted/rejected notifications

* [web] render resolved change previews instead of accepted/rejected count lines

* [web] add unit coverage for accepted/rejected change preview flow

* fix: notification carries multiple previews per accept/reject batch; extract shared group helper

* fix: one preview per accept/reject action, drop adjacency grouping

* fix: move buildResolvedChangePreviews out of the email builder class

* fix: type error, make tests more explicit

* fix: render resolver below preview

* fix: overflow text, alignment

* fix: test error

* fix: resolved count

* [document-updater/web] send sparse change preview instead of full doc lines

* fix: store sparse preview, hydrate at render, drop CE gate

* fix: advance slice cursor past tracked-delete text in sparse preview

* fix: inline buildChangeGroupPreview

* fix: changePreviewBuilder -> sparseChangePreview

* fix: rm change_contributors

* fix: copilot flagged testing issues

* fix: hydrate and truncate change preview at write time

* fix: avoid materializing full doc text when slicing preview window

* fix: update reject preview test to hydrated shape

* fix: accepted delete removing context

* [document-updater/web] split resolved change previews into one per change cluster

* fix: narrow cluster userIds to string[] for typecheck

* feat: updating to use zod schema for previews

---------

Co-authored-by: Jimmy Domagala-Tang <jimmy.domagala-tang@overleaf.com>
GitOrigin-RevId: 0740713c715a61a220180f353e497b27da6a5b0f

services/web/app/src/Features/DocumentUpdater/DocumentUpdaterHandler.mjs

@@ -208,7 +208,7 @@ async function clearProjectState(projectId) {
  * @param {string} userId
  */
 async function acceptChanges(projectId, docId, changeIds, userId) {
-  const { changeContributors } = await fetchJson(
+  const { changeContributors, previews } = await fetchJson(
     `${BASE_URL}/project/${projectId}/doc/${docId}/change/accept`,
     {
       method: 'POST',
@@ -221,7 +221,8 @@ async function acceptChanges(projectId, docId, changeIds, userId) {
     projectId,
     docId,
     userId,
-    changeContributors
+    changeContributors,
+    previews
   )
 }
 

services/web/app/src/Features/Documents/DocumentController.mjs

@@ -214,6 +214,21 @@ async function setDocument(req, res) {
   res.json(result)
 }
 
+const changePreview = z.strictObject({
+  sectionPath: z.array(z.string()),
+  startLine: z.number().int().min(1),
+  changes: z.array(
+    z.strictObject({
+      i: z.string().optional(),
+      d: z.string().optional(),
+      p: z.number().int().min(0),
+    })
+  ),
+  slice: z.string(),
+  sliceStart: z.number().int().min(0),
+  userIds: z.array(zz.objectId()),
+})
+
 const trackChangesRejectedSchema = z.object({
   params: z.strictObject({
     Project_id: zz.objectId(),
@@ -222,6 +237,7 @@ const trackChangesRejectedSchema = z.object({
   body: z.strictObject({
     rejectedChangeAuthorIds: z.array(zz.objectId()),
     userId: zz.objectId().optional(),
+    previews: z.array(changePreview).optional(),
   }),
 })
 
@@ -230,13 +246,14 @@ async function trackChangesRejected(req, res) {
     logOnly: true,
   })
   const { Project_id: projectId, doc_id: docId } = params
-  const { rejectedChangeAuthorIds, userId } = body
+  const { rejectedChangeAuthorIds, userId, previews } = body
   await Modules.promises.hooks.fire(
     'trackChangesRejected',
     projectId,
     docId,
     userId,
-    rejectedChangeAuthorIds
+    rejectedChangeAuthorIds,
+    previews
   )
   res.sendStatus(204)
 }