merge: sync Rongsong's scheduler-framework into chatbot

Full merge of origin/scheduler-framework (scheduler-core restructure,
failover-adoption, WAL_JOB_DISPATCH, apiserver backend health/heartbeat,
build-time versioning, bug-1673/1676/1678/1679/1680).

Conflict resolution:
- scheduler: adopt Rongsong's scheduler-core architecture (driver loop,
  queue project/picker fields, resource bug-1569 fix)
- worker/controller_connector.c: keep Rongsong's reconnect/rejoin
  structure, PORT our bug-1509 resend_job_status onto the rejoin success
  path (his reconnect didn't re-report job state)
- apiserver backend: take Rongsong's health/heartbeat (supersedes our
  e505066 circuit breaker)
- group.c: keep our bug-1513 comment
- misc: take theirs for additive fixes (go_build versioning,
  test_group.c, persist.c RUSAGE_UPDATE, FilterRows bug-1680)

NOTE: our scheduler fixes (bug-1494 family dispatch-fail requeue,
PEND-reason classification) are NOT in Rongsong's branch — needs
verification/porting onto scheduler-core (separate follow-up).

Co-Authored-By: Claude <noreply@anthropic.com>

src/frontend/apiserver/models/jobs.go

@@ -206,7 +206,6 @@ var JOB_DEFAULT_COLUMN = []string{
 	"job_name",
 	"command",
 	"submit_time",
-	"pending_reason",
 }
 
 var ARRAY_JOB_DEFAULT_COLUMN = []string{
@@ -613,7 +612,13 @@ type JobAdditionalFields struct {
 	Pids              []int     `json:"pids"`  // List of process IDs associated with the job
 	Pgids             []int     `json:"pgids"` // List of process group IDs associated with the job
 	InteractiveJobURL string    `json:"interactive_job_url"`
-	PendingReason     Jsonb     `json:"pending_reason"` // PEND reason (scheduler-set, JSONB object)
+	// CoreLimit/MemLimit: JobInfo has no equivalent field (these are
+	// submission-time resource limits, not job-state fields), but xcecli's
+	// JobFieldsMap accepts them as valid -o/-l display fields (bug-1674) --
+	// merged in here rather than validating against JobSubmitRequest itself,
+	// which lacks response-only fields like pending_reason.
+	CoreLimit CustomLimit `json:"core_limit"`
+	MemLimit  CustomLimit `json:"mem_limit"`
 }
 
 type JobSubmitRequest struct {
@@ -657,6 +662,7 @@ type JobSubmitRequest struct {
 	ChkpntDir          string      `json:"chkpnt_dir,omitempty"`
 	InitChkpntPeriod   int         `json:"init_chkpnt_period,omitempty"`
 	CWD                string      `json:"cwd,omitempty"`
+	FromHost           string      `json:"from_host,omitempty"` // client-asserted submitting hostname (bug-1676) -- passed through unchanged, not derived server-side
 	OutDir             string      `json:"out_dir,omitempty"`
 	InFile             string      `json:"in_file,omitempty"`
 	OutFile            string      `json:"out_file,omitempty"`
@@ -697,7 +703,6 @@ type ShellLimit struct {
 
 type JobSubmitResponse struct {
 	JobID     int64  `json:"jobid"`
-	JobIDHuman string `json:"job_id_human"` // cluster-apiserver-timestamp-seq, for xce_test/xcecli cross-reference
 	QueueName string `json:"queue_name"`
 	Message   string `json:"message"`
 }