Coach lineup polish, referee level/position delete, feature-flag nav gating, per-job pause

- Coach line-up screen: more breathing room above the sheet, brighter event
  subtitle, and the "Schedule" button now matches the date input's height.
- Positions and referee levels can now be deleted from Settings (blocked with
  a friendly message if still in use on a roster/referee profile/inheritance
  chain).
- The Evaluations nav placeholder is now gated on the formbuilder flag, same
  as Forms itself, since the design reuses formbuilder underneath.
- Control panel: each scheduled platform job can now be paused/resumed
  individually (features.models.JobToggle), independent of the platform-wide
  Maintenance lock.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

club/tasks.py

@@ -13,7 +13,7 @@ from django.utils import timezone
 
 from club.models import Club
 from club.services.seasons import generate_seasons as generate_seasons_for_club
-from features.models import Maintenance
+from features.models import JobToggle, Maintenance
 
 #: How far ahead to generate, matching the management command's own default.
 YEARS_AHEAD = 2
@@ -23,6 +23,8 @@ YEARS_AHEAD = 2
 def generate_seasons():
     if Maintenance.is_on():
         raise RuntimeError("Platform is in maintenance mode; this job stood down.")
+    if not JobToggle.is_enabled("club.tasks.generate_seasons"):
+        raise RuntimeError("This job is disabled in the control panel.")
 
     until = timezone.localdate() + relativedelta(years=YEARS_AHEAD)
     clubs = Club.objects.active()