Add billing-ending banner, events CRUD, RBIHF import, public API, team photos, and sponsors

A large batch of club-management features built up over one session:

- Club dashboard banner warning admins 1 month before billing ends
- Full Events/EventSeries CRUD (recurrence builder, occurrence lifecycle,
  per-team permissions), with match->game rename and game-specific fields
  (score, competition, live status, external game ID)
- Django-admin competition dropdown, gated per-club by feature flag
- Auto-import of RBIHF fixtures (scrape -> diff -> preview -> confirm),
  with location/opponent dropdowns suggested from existing club data
- Feature-flag-gated Shop/Forms nav sections, reusing the same flag
  machinery for the RBIHF import button
- Team roster now scoped to members active this season or next, sorted and
  grouped by position
- Club sport type (ice hockey / other), shown in the control panel's club
  subtitle
- Per-season team photo upload from the team page
- New public read-only API (Django Ninja) at /api/v1/: news, team rosters,
  upcoming/live/per-team games, and sponsors -- auto-documented via Swagger
  UI, CORS-enabled for a club's own external website
- Club sponsors: admin-only CRUD (logo, URL, active date window) plus a
  date-windowed, optionally randomized API endpoint
- Assorted fixes: NullBooleanField dropdown rendering, cross-club event
  validation timing, searchable-select chip placement, btn-neutral ->
  default button style sweep, calendar-month chart windows

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01R1gj3J1QPfP38XWpnpbFpy

news/api.py

@@ -0,0 +1,83 @@
+"""Public read-only news endpoint -- see api/urls.py for how this is mounted.
+
+Pagination is hand-rolled (limit/offset params) rather than Ninja's built-in
+@paginate: a photo's URL has to be made absolute against `request`
+(api/urls.py's docstring explains why), and Ninja's response-schema resolvers
+don't have request access, so building the page manually here is simpler than
+fighting that.
+"""
+
+import uuid
+from datetime import datetime
+
+from django.utils import timezone
+from ninja import Router, Schema
+
+from api.errors import require_club
+
+from .models import News
+
+router = Router(tags=["news"])
+
+DEFAULT_LIMIT = 20
+MAX_LIMIT = 100
+
+
+class NewsPhotoOut(Schema):
+    url: str
+    is_main: bool
+    ordering: int
+
+
+class NewsItemOut(Schema):
+    id: uuid.UUID
+    title: str
+    slug: str
+    body: str
+    published_at: datetime
+    teams: list[str]
+    photos: list[NewsPhotoOut]
+
+
+class NewsListOut(Schema):
+    count: int
+    limit: int
+    offset: int
+    results: list[NewsItemOut]
+
+
+def _to_news_item_out(item, request) -> NewsItemOut:
+    return NewsItemOut(
+        id=item.pk,
+        title=item.title,
+        slug=item.slug,
+        body=item.body,
+        published_at=item.published_at,
+        teams=[team.name for team in item.teams.all()],
+        photos=[NewsPhotoOut(url=request.build_absolute_uri(photo.image.url), is_main=photo.is_main, ordering=photo.ordering) for photo in item.photos.all()],
+    )
+
+
+@router.get("/", response=NewsListOut, summary="Published news")
+def list_news(request, limit: int = DEFAULT_LIMIT, offset: int = 0):
+    """Published news items whose release date has passed and that are marked
+    visible outside the club (`external` or `both`) -- newest first."""
+    club = require_club(request)
+    limit = max(1, min(limit, MAX_LIMIT))
+    offset = max(0, offset)
+
+    queryset = (
+        News.objects.filter(
+            club=club,
+            status=News.Status.PUBLISHED,
+            published_at__lte=timezone.now(),
+            visibility__in=[News.Visibility.EXTERNAL, News.Visibility.BOTH],
+        )
+        .prefetch_related("photos", "teams")
+        .order_by("-published_at")
+    )
+
+    count = queryset.count()
+    page = queryset[offset : offset + limit]
+
+    return NewsListOut(count=count, limit=limit, offset=offset, results=[_to_news_item_out(item, request) for item in page])