vgsp: stalled-entry detector + opdef-hold deadline fix (GR-STALL-stale-entry)

r228 witness: entry 82 of channel 0x5c000059 stayed pending with
put=84 get=82 last=82 frozen for ~10 s (its 1 MiB op operand never
resolved, sema-optrace rc=-2) while 'sema-opdef: hold entry=82' and
'opdef-clear caller=4 entry=82' repeated: svc_opdef_drop_stale cleared
the opdef slot on every rewind replay that processed a different entry
of the channel, so the 10 s deadline restarted and the hold re-armed
forever (opdef_held climbing, no EXPIRED). No GR-STALL line fired
because this is below the GR-publish layer: the launch never reached a
capture/submit.

- svc_opdef_drop_stale: only a slot whose entry was CONSUMED this put
  epoch (slot_done_epoch bit set by svc_replay_note) is delivered-late
  and dropped. A rewind re-decoding an unconsumed entry no longer resets
  its hold deadline, so the bounded 10 s flush/expiry is reachable
  again.
- svc_gr_stale_wedge_check: new stale-entry leg (reason=stale-entry,
  entry=1) for a genuinely stalled pending entry: GR channel,
  put > get, position AND submissions static for the 3 s window, and no
  bounded owner active (no defer_since grace, no no-capture window, no
  live m150 hold, no opdef slot for the stuck entry). Action is the
  canonical unstuck: last_get = 0 + wd_nocap_put, decode releases only
  (forward-only, no re-capture/re-forward), once per put epoch. No
  residual publish/arm (m181-only rule); r220 hold guard untouched.

Green safety: a green pending entry either advances submissions (consume
within ms) or sets one of the bounded owners the leg gates on; the
stale-entry leg therefore needs all of {put > get, 3 s position stall,
0 consumption, no owner} to fire. make kernel green.

(cherry picked from commit f0789007c49c7c6e01da5643d56ceff0b2b83819)

0 files changed, 0 insertions, 0 deletions