fix(pairing): show actual code in approval command instead of placeholder (#13723)

* fix(pairing): show actual code in approval command instead of placeholder

The pairing reply shown to new users included the approval command with
a literal '<code>' placeholder. Users had to manually copy the code
from one line and substitute it into the command.

Now shows the ready-to-copy command with the real pairing code:

Before: openclaw pairing approve telegram <code>
After:  openclaw pairing approve telegram abc123

Fixed in both the shared pairing message builder and the Telegram
inline pairing reply.

* test(pairing): update test to expect actual code instead of placeholder

---------

Co-authored-by: Echo Ito <echoito@MacBook-Air.local>

src/pairing/pairing-messages.test.ts

@@ -52,7 +52,7 @@ describe("buildPairingReply", () => {
       expect(text).toContain(`Pairing code: ${testCase.code}`);
       // CLI commands should respect OPENCLAW_PROFILE when set (most tests run with isolated profile)
       const commandRe = new RegExp(
-        `(?:openclaw|openclaw) --profile isolated pairing approve ${testCase.channel} <code>`,
+        `(?:openclaw|openclaw) --profile isolated pairing approve ${testCase.channel} ${testCase.code}`,
       );
       expect(text).toMatch(commandRe);
     });