fix(runtime): 运行稳定性 - 修复技能种子、任务续租与回归检查

保留社区技能作者与时间戳修复、Agent 参数约束、资源删除 worker 生命周期、PostgreSQL/Redis 测试门禁及相关回归。

Original-Commit: 0d05ff88bbe6c875d01964041788023a662ff7e8

backend/internal/app/task_worker_test.go

@@ -2,8 +2,12 @@ package app
 
 import (
 	"context"
+	"errors"
 	"testing"
 	"time"
+
+	"infinite-canvas/backend/internal/model"
+	"infinite-canvas/backend/internal/repository"
 )
 
 // 续租必须比"这条任务的执行时限"活得更久：否则父 context 到点时，续租请求会被自己的
@@ -39,3 +43,66 @@ func TestTaskLeaseRenewContextSurvivesExecutionDeadline(t *testing.T) {
 		t.Fatalf("父 context 取消不该连带取消续租 context：%v", err)
 	}
 }
+
+func TestTaskDeadlineRenewalAndTerminalFencing(t *testing.T) {
+	for _, lost := range []bool{false, true} {
+		name := "deadline_with_valid_lease"
+		if lost {
+			name = "deadline_with_reclaimed_lease"
+		}
+		t.Run(name, func(t *testing.T) {
+			db := newSQLiteTestDB(t)
+			if err := db.AutoMigrate(&model.Task{}); err != nil {
+				t.Fatal(err)
+			}
+			repo := repository.New(db)
+			if err := db.Create(&model.Task{ID: "deadline-task", UserID: "user", Type: "canvas_text", Status: model.TaskStatusQueued}).Error; err != nil {
+				t.Fatal(err)
+			}
+			task, err := repo.ClaimNextTask("worker-a", time.Minute)
+			if err != nil || task == nil {
+				t.Fatalf("claim: %v %v", task, err)
+			}
+			ctx, cancel := context.WithDeadline(context.Background(), time.Now().Add(-time.Second))
+			defer cancel()
+			renew, cancelRenew := taskLeaseRenewContext(ctx)
+			defer cancelRenew()
+			if lost {
+				if err := db.Model(&model.Task{}).Where("id = ?", task.ID).Update("lease_expires_at", time.Now().Add(-time.Second)).Error; err != nil {
+					t.Fatal(err)
+				}
+				reclaimed, err := repo.ClaimNextTask("worker-b", time.Minute)
+				if err != nil || reclaimed == nil {
+					t.Fatalf("reclaim: %v %v", reclaimed, err)
+				}
+			}
+			err = repo.WithContext(renew).RenewTaskLease(task.ID, task.LeaseOwner, time.Minute)
+			if (err != nil) != lost {
+				t.Fatalf("renew lost=%v: %v", lost, err)
+			}
+			billing, replay := &taskTerminalBillingStub{}, &taskTerminalReplayStub{}
+			terminal := newTaskTerminalCoordinatorForTest(repo, billing, replay, &taskTerminalLoggerStub{}, &taskTerminalOutputStub{})
+			err = terminal.handleExecutionFailure(task, ctx.Err(), false, false)
+			stored, readErr := repo.Task(task.ID)
+			if readErr != nil {
+				t.Fatal(readErr)
+			}
+			if lost {
+				if !errors.Is(err, repository.ErrTaskStateConflict) || stored.Status != model.TaskStatusRunning || stored.LeaseOwner != "worker-b" {
+					t.Fatalf("stale terminal write: %v %#v", err, stored)
+				}
+				if len(billing.refund)+len(billing.uncertain)+len(replay.statuses) != 0 {
+					t.Fatal("stale worker emitted terminal side effects")
+				}
+			} else {
+				if !errors.Is(err, context.DeadlineExceeded) || stored.Status != model.TaskStatusFailed {
+					t.Fatalf("deadline not finalized: %v %#v", err, stored)
+				}
+				next, err := repo.ClaimNextTask("worker-b", time.Minute)
+				if err != nil || next != nil {
+					t.Fatalf("terminal task reclaimed: %v %v", next, err)
+				}
+			}
+		})
+	}
+}