Use unique contact identifiers for KOC claims

lib/claimant-identifier.ts

@@ -0,0 +1,35 @@
+export type ClaimantIdentifier = {
+  canonical: string;
+  display: string;
+  kind: "phone" | "wechat";
+};
+
+function stripLabel(value: string) {
+  return value
+    .replace(/^(?:微信号|微信|wechat|手机号|手机)\s*[:：]?\s*/i, "")
+    .trim();
+}
+
+export function parseClaimantIdentifier(value: unknown): ClaimantIdentifier | null {
+  const input = stripLabel(String(value ?? "").trim());
+  if (!input) return null;
+
+  const phone = input.replace(/[\s-]/g, "").replace(/^\+?86/, "");
+  if (/^1[3-9]\d{9}$/.test(phone)) {
+    return {
+      canonical: `phone:${phone}`,
+      display: phone,
+      kind: "phone",
+    };
+  }
+
+  if (/^[A-Za-z][A-Za-z0-9_-]{5,31}$/.test(input)) {
+    return {
+      canonical: `wechat:${input.toLowerCase()}`,
+      display: input,
+      kind: "wechat",
+    };
+  }
+
+  return null;
+}