fix: 12h cooldown before reopening manually closed host_silence (0.9.9)

Track resolved_by on problems; suppress scan/ingest recreate after manual
resolve; reopen same problem after cooldown; auto-close via heartbeat unchanged.

Co-authored-by: Cursor <cursoragent@cursor.com>

backend/app/services/problems.py

@@ -10,6 +10,7 @@ from app.models import Event, Problem, ProblemEvent
 from app.services.host_health import HEARTBEAT_TYPE
 from app.services.problem_rules import (
     RuleMatch,
+    RULE_HOST_SILENCE,
     build_fingerprint,
     pick_rule_match,
     resolve_host_silence_problems,
@@ -43,7 +44,21 @@ def _append_event(db: Session, problem: Problem, event: Event) -> None:
 
 def open_or_append_problem(
     db: Session, event: Event, match: RuleMatch
-) -> tuple[Problem, bool]:
+) -> tuple[Problem | None, bool]:
+    if match.rule_id == RULE_HOST_SILENCE:
+        from app.services.host_silence_scan import open_or_refresh_host_silence_problem
+
+        ref = event.occurred_at
+        if ref.tzinfo is None:
+            ref = ref.replace(tzinfo=timezone.utc)
+        problem, created = open_or_refresh_host_silence_problem(
+            db, event.host_id, match, now=ref
+        )
+        if problem is None:
+            return None, False
+        _append_event(db, problem, event)
+        return problem, created
+
     fingerprint = build_fingerprint(
         event.host_id,
         match.correlation_type,
@@ -98,4 +113,5 @@ def maybe_create_problem(db: Session, event: Event) -> tuple[Problem | None, boo
     if match is None:
         return None, False
 
-    return open_or_append_problem(db, event, match)
+    problem, created = open_or_append_problem(db, event, match)
+    return problem, created