feat(ui): platform control panel and styled auth screens

Add the `controlpanel` app: a platform-wide (not club-scoped) admin panel for
creating clubs, archiving/restoring them, managing club admins, and per-club
statistics (members, teams & staff, events, shop). Statistics are annotated in
one query so the club list cannot fan out into N+1, and are returned as stat
*groups* so growing the domain means adding one entry.

Two access rules, both enforced by PlatformStaffRequiredMixin:
- staff only (is_staff/is_superuser); anonymous are sent to login, signed-in
  non-staff get a 403. Staff already need a second factor, so the panel is
  2FA-protected for free.
- base domain only: the panel manages *all* clubs, so it 404s if the tenant
  middleware resolved a club from the subdomain.

Granting admin to an unknown email creates the account (unusable password —
they set one via password reset) and the Member behind it, since a ClubRole
hangs off a Member. A member who already holds a role is promoted in place,
because there is only one role per member per club.

UI is Tailwind + daisyUI. allauth ships an element system, so overriding
allauth/layouts/base.html plus ~13 element partials restyles *every* auth and
2FA screen at once — login, signup, password reset, the 2FA challenge, TOTP
enrolment, passkeys and recovery codes — rather than templating 20+ pages.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

controlpanel/services/statistics.py

@@ -0,0 +1,92 @@
+"""Platform and per-club statistics.
+
+``club_statistics`` returns a list of stat *groups*, so growing the model later
+means adding an entry here and nothing else. ``clubs_with_totals`` annotates in
+a single query — the club list must not fan out into N+1.
+"""
+
+from decimal import Decimal
+
+from django.db.models import Count, Q, Sum
+from django.utils import timezone
+
+from club.models import Club, ClubMembership, ClubRole, Season
+from events.models import Event
+from members.models import Member
+from shop.models import Cart, Order
+from teams.models import StaffAssignment, Team, TeamMembership
+
+ZERO = Decimal("0.00")
+
+PAID_STATUSES = (Order.OrderStatus.PAID, Order.OrderStatus.DELIVERED)
+OWED_STATUSES = (Order.OrderStatus.PENDING, Order.OrderStatus.PARTIALLY_PAID)
+
+
+def clubs_with_totals(queryset=None):
+    """Clubs annotated with headline counts (one query, no N+1)."""
+    clubs = Club.objects.all() if queryset is None else queryset
+    return clubs.annotate(
+        member_count=Count("clubmemberships__member", distinct=True),
+        team_count=Count("teams", distinct=True),
+        event_count=Count("events", distinct=True),
+        admin_count=Count("clubroles", filter=Q(clubroles__role=ClubRole.Roles.ADMIN), distinct=True),
+    )
+
+
+def platform_totals():
+    return {
+        "clubs": Club.objects.active().count(),
+        "archived_clubs": Club.objects.archived().count(),
+        "members": Member.objects.count(),
+        "admins": ClubRole.objects.filter(role=ClubRole.Roles.ADMIN).count(),
+    }
+
+
+def _money(queryset):
+    return queryset.aggregate(total=Sum("total"))["total"] or ZERO
+
+
+def club_statistics(club):
+    """Stat groups for one club. Add new groups here as the domain grows."""
+    season = Season.covering(club, timezone.localdate())
+    now = timezone.now()
+
+    memberships = ClubMembership.objects.filter(club=club)
+    events = Event.objects.filter(club=club)
+    orders = Order.objects.filter(club=club)
+
+    return [
+        {
+            "title": "Members",
+            "stats": [
+                ("Members", memberships.values("member").distinct().count()),
+                ("Active this season", memberships.filter(season=season, status=ClubMembership.StatusChoices.ACTIVE).count() if season else 0),
+                ("Pending", memberships.filter(status=ClubMembership.StatusChoices.PENDING).count()),
+                ("Lapsed", memberships.filter(status=ClubMembership.StatusChoices.LAPSED).count()),
+            ],
+        },
+        {
+            "title": "Teams & staff",
+            "stats": [
+                ("Teams", Team.objects.filter(club=club).count()),
+                ("Players this season", TeamMembership.objects.filter(team__club=club, season=season).count() if season else 0),
+                ("Staff this season", StaffAssignment.objects.filter(team__club=club, season=season).count() if season else 0),
+            ],
+        },
+        {
+            "title": "Events",
+            "stats": [
+                ("Upcoming", events.filter(start__gte=now).count()),
+                ("This season", events.filter(season=season).count() if season else 0),
+            ],
+        },
+        {
+            "title": "Shop",
+            "stats": [
+                ("Orders", orders.count()),
+                ("Revenue", _money(orders.filter(status__in=PAID_STATUSES))),
+                ("Outstanding", _money(orders.filter(status__in=OWED_STATUSES))),
+                ("Open carts", Cart.objects.filter(club=club, status=Cart.CartStatus.OPEN).count()),
+            ],
+        },
+    ]