Show friendly Copilot (AI) name in gh pr view

Add CopilotDisplayName helper that translates known Copilot bot
logins (copilot-pull-request-reviewer, copilot-swe-agent) to the
friendly 'Copilot (AI)' display name. Applied to:

- PullRequestReview.AuthorLogin() — review comment author
- Comment.AuthorLogin() — PR/issue comment author
- parseReviewers() in pr view — reviewer list display

This ensures gh pr view shows 'Copilot (AI)' instead of the raw
'copilot-pull-request-reviewer' login for both the reviewer status
line and any review comments left by Copilot.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

api/queries_comments.go

@@ -129,7 +129,7 @@ func (c Comment) Identifier() string {
 }
 
 func (c Comment) AuthorLogin() string {
-	return c.Author.Login
+	return copilotDisplayName(c.Author.Login)
 }
 
 func (c Comment) Association() string {

api/queries_pr_review.go

@@ -52,7 +52,7 @@ func (prr PullRequestReview) Identifier() string {
 }
 
 func (prr PullRequestReview) AuthorLogin() string {
-	return prr.Author.Login
+	return copilotDisplayName(prr.Author.Login)
 }
 
 func (prr PullRequestReview) Association() string {
@@ -158,8 +158,9 @@ func (r RequestedReviewer) DisplayName() string {
 	if r.TypeName == teamTypeName {
 		return fmt.Sprintf("%s/%s", r.Organization.Login, r.Slug)
 	}
-	if r.TypeName == botTypeName && r.Login == CopilotReviewerLogin {
-		return "Copilot (AI)"
+	displayName := copilotDisplayName(r.Login)
+	if displayName != r.Login {
+		return displayName
 	}
 	if r.Name != "" {
 		return fmt.Sprintf("%s (%s)", r.Login, r.Name)
@@ -221,10 +222,7 @@ func NewReviewerBot(login string) ReviewerBot {
 }
 
 func (b ReviewerBot) DisplayName() string {
-	if b.login == CopilotReviewerLogin {
-		return fmt.Sprintf("%s (AI)", CopilotActorName)
-	}
-	return b.Login()
+	return copilotDisplayName(b.login)
 }
 
 func (r ReviewerBot) sealedReviewerCandidate() {}

api/queries_repo.go

@@ -1087,6 +1087,16 @@ const CopilotAssigneeLogin = "copilot-swe-agent"
 const CopilotReviewerLogin = "copilot-pull-request-reviewer"
 const CopilotActorName = "Copilot"
 
+// copilotDisplayName returns "Copilot (AI)" if the login is a known Copilot bot login,
+// otherwise returns the login unchanged. Use this to translate raw bot logins into
+// user-friendly display names in command output.
+func copilotDisplayName(login string) string {
+	if login == CopilotReviewerLogin || login == CopilotAssigneeLogin {
+		return fmt.Sprintf("%s (AI)", CopilotActorName)
+	}
+	return login
+}
+
 type AssignableActor interface {
 	DisplayName() string
 	ID() string
@@ -1145,10 +1155,7 @@ func NewAssignableBot(id, login string) AssignableBot {
 }
 
 func (b AssignableBot) DisplayName() string {
-	if b.login == CopilotAssigneeLogin {
-		return fmt.Sprintf("%s (AI)", CopilotActorName)
-	}
-	return b.Login()
+	return copilotDisplayName(b.login)
 }
 
 func (b AssignableBot) ID() string {

api/queries_repo_test.go

@@ -563,6 +563,26 @@ func TestDisplayName(t *testing.T) {
 	}
 }
 
+func TestCopilotDisplayName(t *testing.T) {
+	tests := []struct {
+		login string
+		want  string
+	}{
+		{login: "copilot-pull-request-reviewer", want: "Copilot (AI)"},
+		{login: "copilot-swe-agent", want: "Copilot (AI)"},
+		{login: "octocat", want: "octocat"},
+		{login: "", want: ""},
+	}
+	for _, tt := range tests {
+		t.Run(tt.login, func(t *testing.T) {
+			got := copilotDisplayName(tt.login)
+			if got != tt.want {
+				t.Errorf("copilotDisplayName(%q) = %q, want %q", tt.login, got, tt.want)
+			}
+		})
+	}
+}
+
 func TestRepoExists(t *testing.T) {
 	tests := []struct {
 		name       string