fix(site): center warning boxes on task error pages

Change min-h-80 to h-full for error containers in TaskPage to properly
center warning boxes vertically. This fixes the layout issue where
warning boxes were not centered when viewing error states such as
accessing another user's task (404 error).

The fix applies to:
- Error loading task state
- Task build failed state
- Workspace not running state

Fixes #20369

site/src/pages/TaskPage/TaskPage.tsx

@@ -77,7 +77,7 @@ const TaskPage = () => {
 			<TaskPageLayout>
 				<title>{pageTitle("Error loading task")}</title>
 
-				<div className="w-full min-h-80 flex items-center justify-center">
+				<div className="w-full h-full flex items-center justify-center">
 					<div className="flex flex-col items-center">
 						<h3 className="m-0 font-medium text-content-primary text-base">
 							{getErrorMessage(error, "Failed to load task")}
@@ -119,7 +119,7 @@ const TaskPage = () => {
 		content = <TaskBuildingWorkspace task={task} />;
 	} else if (task.workspace.latest_build.status === "failed") {
 		content = (
-			<div className="w-full min-h-80 flex items-center justify-center">
+			<div className="w-full h-full flex items-center justify-center">
 				<div className="flex flex-col items-center">
 					<h3 className="m-0 font-medium text-content-primary text-base">
 						Task build failed
@@ -218,7 +218,7 @@ const WorkspaceNotRunning: FC<WorkspaceNotRunningProps> = ({ task }) => {
 
 	return (
 		<Margins>
-			<div className="w-full min-h-80 flex items-center justify-center">
+			<div className="w-full h-full flex items-center justify-center">
 				<div className="flex flex-col items-center">
 					<h3 className="m-0 font-medium text-content-primary text-base">
 						Workspace is not running