[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/document-updater/test/unit/js/UpdateManager/UpdateManagerTests.js

@@ -92,6 +92,7 @@ describe('UpdateManager', function () {
       },
     }
 
+    this.buildSparseChangePreviews = sinon.stub().returns([])
     this.UpdateManager = SandboxedModule.require(MODULE_PATH, {
       requires: {
         './ProjectLockManager': this.ProjectLockManager,
@@ -107,6 +108,9 @@ describe('UpdateManager', function () {
         './WebApiManager': this.WebApiManager,
         './Profiler': this.Profiler,
         './ProjectHistoryRedisManager': this.ProjectHistoryRedisManager,
+        './TrackedChangePreview': {
+          buildSparseChangePreviews: this.buildSparseChangePreviews,
+        },
       },
     })
   })
@@ -610,6 +614,17 @@ describe('UpdateManager', function () {
           historyUpdates: this.historyUpdates,
           removedChangeIds: ['change-1', 'change-2'],
         })
+        this.mockPreviews = [
+          {
+            sectionPath: ['Intro'],
+            startLine: 1,
+            changes: [{ d: 'x', p: 0 }],
+            slice: 'x',
+            sliceStart: 0,
+            userIds: ['author-1', 'author-2'],
+          },
+        ]
+        this.buildSparseChangePreviews.returns(this.mockPreviews)
         await this.UpdateManager.promises.applyUpdate(
           this.project_id,
           this.doc_id,
@@ -617,12 +632,23 @@ describe('UpdateManager', function () {
         )
       })
 
-      it('should notify web of the rejected tracked changes', function () {
+      it('should call buildSparseChangePreviews with the rejected changes and lines', function () {
+        this.buildSparseChangePreviews.should.have.been.calledWith({
+          changes: [
+            { id: 'change-1', metadata: { user_id: 'author-1' } },
+            { id: 'change-2', metadata: { user_id: 'author-2' } },
+          ],
+          lines: this.lines,
+        })
+      })
+
+      it('should notify web of the rejected tracked changes with the previews', function () {
         this.WebApiManager.promises.notifyTrackChangesRejected.should.have.been.calledWith(
           this.project_id,
           this.doc_id,
           this.rejectedChangeAuthorIds,
-          this.updateMeta.user_id
+          this.updateMeta.user_id,
+          this.mockPreviews
         )
       })
     })