refactor: dedupe cli lowercase helpers

src/cli/pairing-cli.ts

@@ -9,6 +9,7 @@ import {
   type PairingChannel,
 } from "../pairing/pairing-store.js";
 import { defaultRuntime } from "../runtime.js";
+import { normalizeLowercaseStringOrEmpty } from "../shared/string-coerce.js";
 import { formatDocsLink } from "../terminal/links.js";
 import { getTerminalTableWidth, renderTable } from "../terminal/table.js";
 import { theme } from "../terminal/theme.js";
@@ -16,15 +17,14 @@ import { formatCliCommand } from "./command-format.js";
 
 /** Parse channel, allowing extension channels not in core registry. */
 function parseChannel(raw: unknown, channels: PairingChannel[]): PairingChannel {
-  const value = (
-    typeof raw === "string"
+  const value = normalizeLowercaseStringOrEmpty(
+    (typeof raw === "string"
       ? raw
       : typeof raw === "number" || typeof raw === "boolean"
         ? String(raw)
         : ""
-  )
-    .trim()
-    .toLowerCase();
+    ).trim(),
+  );
   if (!value) {
     throw new Error("Channel required");
   }