fix(coderd/database): improve task status in tasks_with_status view (#20683)

This change restructures the `tasks_with_status` view query to:

- Improve debuggability by adding a `status_debug` column to better
understand the outcome
- Reduce clutter from `bool_or`, `bool_and` which are aggregate
functions that did not actually have serve a purpose (each join is 0-1
rows)
- Improve agent lifecycle state coverage, `start_timeout` and
`start_error` were omitted
- These states are easy to trigger even in a perfectly functioning
workspace/task so we now rely on app health to report whether or not
there was an issue
- Mark canceling and canceled workspace build jobs as error state
- Agent stop states were implicitly `unknown`, now there are explicit (I
initially considered `error`, could go either way)

coderd/database/querier_test.go

@@ -6664,6 +6664,23 @@ func TestTasksWithStatusView(t *testing.T) {
 				StartedAt:      sql.NullTime{Valid: true, Time: dbtime.Now()},
 				CompletedAt:    sql.NullTime{Valid: true, Time: dbtime.Now()},
 			}
+		case database.ProvisionerJobStatusCanceling:
+			jobParams = database.ProvisionerJob{
+				OrganizationID: org.ID,
+				Type:           database.ProvisionerJobTypeWorkspaceBuild,
+				InitiatorID:    user.ID,
+				StartedAt:      sql.NullTime{Valid: true, Time: dbtime.Now()},
+				CanceledAt:     sql.NullTime{Valid: true, Time: dbtime.Now()},
+			}
+		case database.ProvisionerJobStatusCanceled:
+			jobParams = database.ProvisionerJob{
+				OrganizationID: org.ID,
+				Type:           database.ProvisionerJobTypeWorkspaceBuild,
+				InitiatorID:    user.ID,
+				StartedAt:      sql.NullTime{Valid: true, Time: dbtime.Now()},
+				CompletedAt:    sql.NullTime{Valid: true, Time: dbtime.Now()},
+				CanceledAt:     sql.NullTime{Valid: true, Time: dbtime.Now()},
+			}
 		default:
 			t.Errorf("invalid build status: %v", buildStatus)
 		}
@@ -6816,6 +6833,28 @@ func TestTasksWithStatusView(t *testing.T) {
 			expectWorkspaceAgentValid: false,
 			expectWorkspaceAppValid:   false,
 		},
+		{
+			name:                      "CancelingBuild",
+			buildStatus:               database.ProvisionerJobStatusCanceling,
+			buildTransition:           database.WorkspaceTransitionStart,
+			expectedStatus:            database.TaskStatusError,
+			description:               "Latest workspace build is canceling",
+			expectBuildNumberValid:    true,
+			expectBuildNumber:         1,
+			expectWorkspaceAgentValid: false,
+			expectWorkspaceAppValid:   false,
+		},
+		{
+			name:                      "CanceledBuild",
+			buildStatus:               database.ProvisionerJobStatusCanceled,
+			buildTransition:           database.WorkspaceTransitionStart,
+			expectedStatus:            database.TaskStatusError,
+			description:               "Latest workspace build was canceled",
+			expectBuildNumberValid:    true,
+			expectBuildNumber:         1,
+			expectWorkspaceAgentValid: false,
+			expectWorkspaceAppValid:   false,
+		},
 		{
 			name:                      "StoppedWorkspace",
 			buildStatus:               database.ProvisionerJobStatusSucceeded,
@@ -6943,24 +6982,26 @@ func TestTasksWithStatusView(t *testing.T) {
 			buildStatus:               database.ProvisionerJobStatusSucceeded,
 			buildTransition:           database.WorkspaceTransitionStart,
 			agentState:                database.WorkspaceAgentLifecycleStateStartTimeout,
-			expectedStatus:            database.TaskStatusUnknown,
-			description:               "Agent start timed out",
+			appHealths:                []database.WorkspaceAppHealth{database.WorkspaceAppHealthHealthy},
+			expectedStatus:            database.TaskStatusActive,
+			description:               "Agent start timed out but app is healthy, defer to app",
 			expectBuildNumberValid:    true,
 			expectBuildNumber:         1,
 			expectWorkspaceAgentValid: true,
-			expectWorkspaceAppValid:   false,
+			expectWorkspaceAppValid:   true,
 		},
 		{
 			name:                      "AgentStartError",
 			buildStatus:               database.ProvisionerJobStatusSucceeded,
 			buildTransition:           database.WorkspaceTransitionStart,
 			agentState:                database.WorkspaceAgentLifecycleStateStartError,
-			expectedStatus:            database.TaskStatusUnknown,
-			description:               "Agent failed to start",
+			appHealths:                []database.WorkspaceAppHealth{database.WorkspaceAppHealthHealthy},
+			expectedStatus:            database.TaskStatusActive,
+			description:               "Agent start failed but app is healthy, defer to app",
 			expectBuildNumberValid:    true,
 			expectBuildNumber:         1,
 			expectWorkspaceAgentValid: true,
-			expectWorkspaceAppValid:   false,
+			expectWorkspaceAppValid:   true,
 		},
 		{
 			name:                      "AgentShuttingDown",
@@ -7081,6 +7122,8 @@ func TestTasksWithStatusView(t *testing.T) {
 			got, err := db.GetTaskByID(ctx, task.ID)
 			require.NoError(t, err)
 
+			t.Logf("Task status debug: %s", got.StatusDebug)
+
 			require.Equal(t, tt.expectedStatus, got.Status)
 
 			require.Equal(t, tt.expectBuildNumberValid, got.WorkspaceBuildNumber.Valid)