fix(task): prevent duplicate Slurm job submission on backend restart

RecoverStuckTasks now skips tasks that already have a slurm_job_id,
and ProcessTask adds a guard before the submitting step to prevent
re-submission even if a task is incorrectly re-enqueued.

Also deprecates POST /api/v1/jobs/submit endpoint (replaced by POST /tasks)
and comments out related handlers and tests.

internal/server/server.go

@@ -10,7 +10,7 @@ import (
 )
 
 type JobHandler interface {
-	SubmitJob(c *gin.Context)
+	// SubmitJob(c *gin.Context) // [已弃用] 已被 POST /tasks 取代
 	GetJobs(c *gin.Context)
 	GetJobHistory(c *gin.Context)
 	GetJob(c *gin.Context)
@@ -73,7 +73,7 @@ func NewRouter(jobH JobHandler, clusterH ClusterHandler, appH ApplicationHandler
 	v1 := r.Group("/api/v1")
 
 	jobs := v1.Group("/jobs")
-	jobs.POST("/submit", jobH.SubmitJob)
+	// jobs.POST("/submit", jobH.SubmitJob) // [已弃用] 已被 POST /tasks 取代
 	jobs.GET("", jobH.GetJobs)
 	jobs.GET("/history", jobH.GetJobHistory)
 	jobs.GET("/:id", jobH.GetJob)
@@ -144,7 +144,7 @@ func NewTestRouter() *gin.Engine {
 
 func registerPlaceholderRoutes(v1 *gin.RouterGroup) {
 	jobs := v1.Group("/jobs")
-	jobs.POST("/submit", notImplemented)
+	// jobs.POST("/submit", notImplemented) // [已弃用] 已被 POST /tasks 取代
 	jobs.GET("", notImplemented)
 	jobs.GET("/history", notImplemented)
 	jobs.GET("/:id", notImplemented)

internal/server/server_test.go

@@ -17,7 +17,7 @@ func TestAllRoutesRegistered(t *testing.T) {
 		method string
 		path   string
 	}{
-		{"POST", "/api/v1/jobs/submit"},
+		// {"POST", "/api/v1/jobs/submit"}, // [已弃用] 已被 POST /tasks 取代
 		{"GET", "/api/v1/jobs"},
 		{"GET", "/api/v1/jobs/history"},
 		{"GET", "/api/v1/jobs/:id"},