Add registration flow and improve admin post management

lib/opc.ts

@@ -0,0 +1,23 @@
+export const OPC_SIGNAL_VALUES = ["solo-feed"] as const;
+
+export type OpcSignalValue = (typeof OPC_SIGNAL_VALUES)[number];
+
+export const OPC_SIGNAL_LABELS: Record<OpcSignalValue, string> = {
+  "solo-feed": "solo-feed"
+};
+
+export const DEFAULT_OPC_SIGNAL: OpcSignalValue = "solo-feed";
+
+const OPC_SIGNAL_SET = new Set<string>(OPC_SIGNAL_VALUES);
+
+export function isOpcSignal(value?: string | null): value is OpcSignalValue {
+  if (!value) return false;
+  return OPC_SIGNAL_SET.has(value);
+}
+
+export function getOpcSignalLabel(value?: string | null): string {
+  if (value && OPC_SIGNAL_SET.has(value)) {
+    return OPC_SIGNAL_LABELS[value as OpcSignalValue];
+  }
+  return OPC_SIGNAL_LABELS[DEFAULT_OPC_SIGNAL];
+}