Fix add_comment_to_pending_review for fork PRs

The addPullRequestReviewThread GraphQL mutation requires the PullRequestID
field to correctly identify the pull request context for fork PRs. Without
this field, the API returns null for the thread ID, causing comments to fail.

This adds the PullRequestID to both the query (to fetch it) and the mutation
input, fixing the issue for fork-based pull requests.

Fixes #1748

Author: SamMorrowDrums

pkg/github/pullrequests.go

@@ -1743,6 +1743,7 @@ func AddCommentToPendingReview(t translations.TranslationHelperFunc) inventory.S
 			var getLatestReviewForViewerQuery struct {
 				Repository struct {
 					PullRequest struct {
+						ID      githubv4.ID
 						Reviews struct {
 							Nodes []struct {
 								ID    githubv4.ID
@@ -1788,6 +1789,7 @@ func AddCommentToPendingReview(t translations.TranslationHelperFunc) inventory.S
 				} `graphql:"addPullRequestReviewThread(input: $input)"`
 			}
 
+			pullRequestID := getLatestReviewForViewerQuery.Repository.PullRequest.ID
 			if err := client.Mutate(
 				ctx,
 				&addPullRequestReviewThreadMutation,
@@ -1799,6 +1801,7 @@ func AddCommentToPendingReview(t translations.TranslationHelperFunc) inventory.S
 					Side:                newGQLStringlikePtr[githubv4.DiffSide](params.Side),
 					StartLine:           newGQLIntPtr(params.StartLine),
 					StartSide:           newGQLStringlikePtr[githubv4.DiffSide](params.StartSide),
+					PullRequestID:       &pullRequestID,
 					PullRequestReviewID: &review.ID,
 				},
 				nil,

pkg/github/pullrequests_test.go

@@ -2731,6 +2731,7 @@ func TestAddPullRequestReviewCommentToPendingReview(t *testing.T) {
 					owner:  "owner",
 					repo:   "repo",
 					prNum:  42,
+					prID:   "PR_kwDOTest123",
 
 					reviews: []getLatestPendingReviewQueryReview{
 						{
@@ -2756,6 +2757,7 @@ func TestAddPullRequestReviewCommentToPendingReview(t *testing.T) {
 						Side:                githubv4mock.Ptr(githubv4.DiffSideRight),
 						StartLine:           githubv4.NewInt(5),
 						StartSide:           githubv4mock.Ptr(githubv4.DiffSideRight),
+						PullRequestID:       githubv4.NewID("PR_kwDOTest123"),
 						PullRequestReviewID: githubv4.NewID("PR_kwDODKw3uc6WYN1T"),
 					},
 					nil,
@@ -2788,6 +2790,7 @@ func TestAddPullRequestReviewCommentToPendingReview(t *testing.T) {
 					owner:  "owner",
 					repo:   "repo",
 					prNum:  42,
+					prID:   "PR_kwDOTest123",
 
 					reviews: []getLatestPendingReviewQueryReview{
 						{
@@ -2813,6 +2816,7 @@ func TestAddPullRequestReviewCommentToPendingReview(t *testing.T) {
 						Side:                githubv4mock.Ptr(githubv4.DiffSideRight),
 						StartLine:           nil,
 						StartSide:           nil,
+						PullRequestID:       githubv4.NewID("PR_kwDOTest123"),
 						PullRequestReviewID: githubv4.NewID("PR_kwDODKw3uc6WYN1T"),
 					},
 					nil,
@@ -3183,11 +3187,57 @@ type getLatestPendingReviewQueryParams struct {
 	owner  string
 	repo   string
 	prNum  int32
+	prID   string // Optional: include PR ID when needed for AddPullRequestReviewThread mutation
 
 	reviews []getLatestPendingReviewQueryReview
 }
 
 func getLatestPendingReviewQuery(p getLatestPendingReviewQueryParams) githubv4mock.Matcher {
+	// If prID is provided, include it in the query structure (needed for AddPullRequestReviewThread)
+	if p.prID != "" {
+		return githubv4mock.NewQueryMatcher(
+			struct {
+				Repository struct {
+					PullRequest struct {
+						ID      githubv4.ID
+						Reviews struct {
+							Nodes []struct {
+								ID    githubv4.ID
+								State githubv4.PullRequestReviewState
+								URL   githubv4.URI
+							}
+						} `graphql:"reviews(first: 1, author: $author)"`
+					} `graphql:"pullRequest(number: $prNum)"`
+				} `graphql:"repository(owner: $owner, name: $name)"`
+			}{},
+			map[string]any{
+				"author": githubv4.String(p.author),
+				"owner":  githubv4.String(p.owner),
+				"name":   githubv4.String(p.repo),
+				"prNum":  githubv4.Int(p.prNum),
+			},
+			githubv4mock.DataResponse(
+				map[string]any{
+					"repository": map[string]any{
+						"pullRequest": map[string]any{
+							"id": p.prID,
+							"reviews": map[string]any{
+								"nodes": []any{
+									map[string]any{
+										"id":    p.reviews[0].id,
+										"state": p.reviews[0].state,
+										"url":   p.reviews[0].url,
+									},
+								},
+							},
+						},
+					},
+				},
+			),
+		)
+	}
+
+	// Default: without PR ID (for SubmitPendingPullRequestReview and DeletePendingPullRequestReview)
 	return githubv4mock.NewQueryMatcher(
 		struct {
 			Repository struct {