feat(web): playout alternate-schedule and template editors on the REST API (#144 S6 (#162))

Adds two sub-path editors under the Playouts screen:
- /app/playouts/{id}/alternate-schedules (Classic playouts)
- /app/playouts/{id}/templates (Block playouts)

Each has a reorderable priority table (up/down/delete) plus a selected-row
detail panel: schedule or template+deco-template pickers, a limit-to-date-range
toggle gating month/day/year selects, and day-of-week / day-of-month / month
multi-select chips with Weekdays/Weekends helpers. Entry points on the playout
card are kind-gated. The Block playout card also gets a default-deco select
wired to PUT /api/playouts/{id}/deco, using the new decoName read field.

DayOfWeek is overridden to day-name strings in the API client (the wire format
is Newtonsoft StringEnumConverter, though the OpenAPI schema types it as number).
Deviations from Blazor: chip multi-select instead of MudSelect, flat grouped
template pickers instead of a group->item cascade, a shorter year range, and the
template calendar preview is omitted.

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

web/src/shell.css

@@ -3711,3 +3711,26 @@
   height: 16px;
   color: var(--action-primary);
 }
+
+/* Playout alternate-schedule / template editors: multi-select day/month chips */
+.ctv-chip-toggle {
+  padding: 3px 9px;
+  border-radius: 999px;
+  border: 1px solid var(--ctv-border);
+  background: var(--ctv-surface);
+  color: var(--ctv-text-soft);
+  font-size: 12px;
+  line-height: 1.4;
+  cursor: pointer;
+  transition: background 0.12s ease, color 0.12s ease, border-color 0.12s ease;
+}
+
+.ctv-chip-toggle:hover {
+  border-color: var(--ctv-accent);
+}
+
+.ctv-chip-toggle-active {
+  background: var(--ctv-accent-soft);
+  border-color: var(--ctv-accent);
+  color: var(--ctv-text);
+}