Build the D5 events calendar, redesign event forms, and polish the events UI

Adds the Week/Month/Season calendar to the Events page (team/group-scoped
visibility, kind-colored blocks, a repeating-series indicator) alongside the
existing table as a List view, and redesigns event/event-series creation
around a kind-first picker with progressive disclosure instead of one long
flat form. Also: an accessible radio-based kind picker (no redundant
select-next-to-cards), a fixed week-grid layout bug, a filterable single-list
redesign of the event detail page's RSVP/responses modal, a tidied-up
recurrence field layout, and assorted button/field height and width fixes
across the referee panel and event forms.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01ECGMEwrc2k4D8VQuwjstj9

static/css/app.css

@@ -3708,6 +3708,9 @@
   .max-h-60 {
     max-height: calc(var(--spacing) * 60);
   }
+  .max-h-96 {
+    max-height: calc(var(--spacing) * 96);
+  }
   .min-h-6 {
     min-height: calc(var(--spacing) * 6);
   }
@@ -3795,6 +3798,9 @@
   .w-full {
     width: 100%;
   }
+  .w-px {
+    width: 1px;
+  }
   .max-w-2xl {
     max-width: var(--container-2xl);
   }
@@ -3840,6 +3846,9 @@
   .flex-1 {
     flex: 1;
   }
+  .flex-shrink {
+    flex-shrink: 1;
+  }
   .shrink {
     flex-shrink: 1;
   }
@@ -5054,6 +5063,11 @@
       width: calc(var(--spacing) * 16);
     }
   }
+  .sm\:w-44 {
+    @media (width >= 40rem) {
+      width: calc(var(--spacing) * 44);
+    }
+  }
   .sm\:grid-cols-2 {
     @media (width >= 40rem) {
       grid-template-columns: repeat(2, minmax(0, 1fr));
@@ -5141,6 +5155,11 @@
       grid-template-columns: repeat(3, minmax(0, 1fr));
     }
   }
+  .xl\:grid-cols-4 {
+    @media (width >= 80rem) {
+      grid-template-columns: repeat(4, minmax(0, 1fr));
+    }
+  }
   .xl\:grid-cols-\[1\.6fr_1fr\] {
     @media (width >= 80rem) {
       grid-template-columns: 1.6fr 1fr;