fix(ui): Display the full assignee name (#89504)

Display the full label for the actor in issue details


![image](https://github.com/user-attachments/assets/8698c522-0027-4218-8d11-4a7407013fe7)

Author: leeandher

static/app/components/group/assigneeSelector.tsx

@@ -23,6 +23,7 @@ interface AssigneeSelectorProps {
   additionalMenuFooterItems?: React.ReactNode;
   memberList?: User[];
   owners?: Array<Omit<SuggestedAssignee, 'assignee'>>;
+  showLabel?: boolean;
 }
 
 export type OnAssignCallback = (
@@ -79,6 +80,7 @@ export function AssigneeSelector({
   handleAssigneeChange,
   owners,
   additionalMenuFooterItems,
+  showLabel = false,
 }: AssigneeSelectorProps) {
   const theme = useTheme();
 
@@ -108,6 +110,7 @@ export function AssigneeSelector({
               })?.type
             }
             loading={assigneeLoading}
+            showLabel={showLabel}
             chevronDirection={isOpen ? 'up' : 'down'}
           />
         </StyledDropdownButton>

static/app/views/issueDetails/streamline/header/assigneeSelector.tsx

@@ -64,6 +64,7 @@ export function GroupHeaderAssigneeSelector({
       owners={owners}
       assigneeLoading={assigneeLoading}
       handleAssigneeChange={handleAssigneeChange}
+      showLabel
       additionalMenuFooterItems={
         <Button
           type="button"

static/app/views/issueDetails/streamline/header/header.spec.tsx

@@ -1,3 +1,4 @@
+import {ActorFixture} from 'sentry-fixture/actor';
 import {GroupFixture} from 'sentry-fixture/group';
 import {OrganizationFixture} from 'sentry-fixture/organization';
 import {ProjectFixture} from 'sentry-fixture/project';
@@ -29,7 +30,15 @@ describe('StreamlinedGroupHeader', () => {
     platform: 'javascript',
     teams: [TeamFixture()],
   });
-  const group = GroupFixture({issueCategory: IssueCategory.ERROR, isUnhandled: true});
+  const group = GroupFixture({
+    issueCategory: IssueCategory.ERROR,
+    isUnhandled: true,
+    assignedTo: ActorFixture({
+      id: '101',
+      email: '[email protected]',
+      name: 'Leander',
+    }),
+  });
   const router = RouterFixture();
 
   describe('JS Project Error Issue', () => {
@@ -94,6 +103,7 @@ describe('StreamlinedGroupHeader', () => {
       expect(
         screen.getByRole('button', {name: 'Modify issue assignee'})
       ).toBeInTheDocument();
+      expect(screen.getByText('Leander')).toBeInTheDocument();
       expect(
         screen.getByRole('button', {name: 'Manage issue experience'})
       ).toBeInTheDocument();