billboard applets: single-root wrapper for HTMX swap; full context on toggle — TDD

- _applets.html wraps menu + container in one #id_billboard_applets_wrapper div; form's hx-target is now the wrapper, so OK no longer leaves a stale duplicate menu in the DOM (which previously caused the next OK to revert prior toggles)
- toggle_billboard_applets passes full context (recent_room, recent_events, viewer, my_rooms) via factored _billboard_context helper, so Most Recent + My Scrolls keep their content after a toggle instead of falling through to the empty fallback
- applets.js: register id_billboard_applets_wrapper as an applet container so post-swap menu cleanup runs
- BillboardAppletsTest: portrait viewport in setUp; FT covers content preservation, no-revert on second toggle, & post-refresh state
- 4 new ITs: Most Recent renders Coin-on-a-String after toggle; My Scrolls renders room name; response has single menu div; second toggle preserves prior hidden state

Code architected by Disco DeDisco <discodedisco@outlook.com>
Git commit message Co-Authored-By:
Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/apps/billboard/views.py

@@ -28,13 +28,12 @@ def _recent_posts(user, limit=3):
     )
 
 
-@login_required(login_url="/")
-def billboard(request):
-    my_rooms = rooms_for_user(request.user).order_by("-created_at")
+def _billboard_context(user):
+    my_rooms = rooms_for_user(user).order_by("-created_at")
 
     recent_room = (
         Room.objects.filter(
-            Q(owner=request.user) | Q(gate_slots__gamer=request.user)
+            Q(owner=user) | Q(gate_slots__gamer=user)
         )
         .annotate(last_event=Max("events__timestamp"))
         .filter(last_event__isnull=False)
@@ -53,14 +52,21 @@ def billboard(request):
         if recent_room else []
     )
 
-    return render(request, "apps/billboard/billboard.html", {
+    return {
         "my_rooms": my_rooms,
         "recent_room": recent_room,
         "recent_events": recent_events,
-        "viewer": request.user,
-        "applets": applet_context(request.user, "billboard"),
+        "viewer": user,
+        "applets": applet_context(user, "billboard"),
         "form": LineForm(),
-        "recent_posts": _recent_posts(request.user),
+        "recent_posts": _recent_posts(user),
+    }
+
+
+@login_required(login_url="/")
+def billboard(request):
+    return render(request, "apps/billboard/billboard.html", {
+        **_billboard_context(request.user),
         "page_class": "page-billboard",
     })
 
@@ -70,11 +76,11 @@ def toggle_billboard_applets(request):
     checked = request.POST.getlist("applets")
     apply_applet_toggle(request.user, "billboard", checked)
     if request.headers.get("HX-Request"):
-        return render(request, "apps/billboard/_partials/_applets.html", {
-            "applets": applet_context(request.user, "billboard"),
-            "form": LineForm(),
-            "recent_posts": _recent_posts(request.user),
-        })
+        return render(
+            request,
+            "apps/billboard/_partials/_applets.html",
+            _billboard_context(request.user),
+        )
     return redirect("billboard:billboard")