Fix syndic cluster mode timeout by enabling /new event forwarding

This fixes a regression introduced in commit 0643102 that prevented
Salt CLI from exiting promptly when using syndics in cluster mode, causing
200+ second timeouts instead of the expected ~15 second completion.

The issue had TWO related bugs:

1. **Syndic event forwarding logic (salt/minion.py)**
   - The syndic was setting return_event=False for ALL events with matching
     master_id, including /new events with minions lists
   - Changed to only set return_event=False for job RETURN events
   - Fixed salt.utils.jid.is_jid(mtag) check which failed for event tags
     like "salt/job/{jid}/new" (checks if entire string is JID, not if it
     contains one)
   - Now uses job_event variable which correctly identifies job events

2. **Master event blacklist logic (salt/daemons/masterapi.py)**
   - Minion event blacklist includes "salt/job/*/new" to prevent minions
     from spoofing job events
   - When syndics forward events with pretag="syndic/{id}", the pretagged
     event should bypass the blacklist as "syndic/{id}/salt/job/{jid}/new"
   - Bug: The `continue` statement skipped BOTH the original event AND
     the pretagged event when original tag was blacklisted
   - Fix: Fire pretagged event BEFORE checking blacklist, so syndic events
     are always forwarded with syndic/ prefix even if original tag is
     blacklisted

Result:
- Master of Masters now receives minions list from syndic via
  syndic/{id}/salt/job/{jid}/new events
- Early-exit logic can trigger when all expected returns are received
- test_syndic_target_single_minion now passes in ~40s instead of timing
  out at 200s

Author: dwoz

salt/daemons/masterapi.py

@@ -816,15 +816,19 @@ def _minion_event(self, load):
                     event_data = event["data"]
                 else:
                     event_data = event
-                if not valid_minion_tag(event["tag"]):
-                    log.warning("Filtering blacklisted event tag %s", event["tag"])
-                    continue
-                self.event.fire_event(event_data, event["tag"])  # old dup event
+                # Fire pretagged event first (for syndics) before blacklist check
+                # This allows syndics to forward events like salt/job/*/new with
+                # the syndic/ prefix, bypassing the minion event blacklist
                 if load.get("pretag") is not None:
                     self.event.fire_event(
                         event_data,
                         salt.utils.event.tagify(event["tag"], base=load["pretag"]),
                     )
+                # Check blacklist for original tag
+                if not valid_minion_tag(event["tag"]):
+                    log.warning("Filtering blacklisted event tag %s", event["tag"])
+                    continue
+                self.event.fire_event(event_data, event["tag"])  # old dup event
         else:
             tag = load["tag"]
             self.event.fire_event(load, tag)

salt/minion.py

@@ -3901,8 +3901,14 @@ async def _process_event(self, raw):
         ):
             job_event = True
 
-        if self.syndic_mode == "cluster" and data.get("master_id", 0) == self.opts.get(
-            "master_id", 1
+        # Only skip forwarding job RETURN events with matching master_id
+        # We must still forward /new events with minion lists so the master
+        # of masters knows which minions to expect returns from
+        if (
+            job_event
+            and tag_parts[3] == "ret"
+            and self.syndic_mode == "cluster"
+            and data.get("master_id", 0) == self.opts.get("master_id", 1)
         ):
             return_event = False
 
@@ -3952,7 +3958,7 @@ async def _process_event(self, raw):
                 # Even in cluster mode we need to forward the raw event with the minions
                 # list to determine which minions we expect to return on the master of masters.
                 or (
-                    return_event and (salt.utils.jid.is_jid(mtag) and "minions" in data)
+                    return_event and job_event and "minions" in data
                 )
             ):
                 # Add generic event aggregation here