docs(web): drop stale pair-account-panel note from Telnet pane

The Telnet method pane still said "After a successful migration a
Pair Account panel will appear below this one" — but pair-account-pane
was removed three commits ago when pairing was folded into the Plan
card as a configured-up-front step that runs as part of Apply. The
note pointed users at a panel that no longer exists.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

pkg/service/handlers/web/index.html

@@ -1022,13 +1022,6 @@
                     install a custom CA. If you need end-to-end TLS, use the
                     XML or DNS method instead.
                 </p>
-                <p style="margin: 5px 0; font-size: 0.9em; color: #555">
-                    After a successful migration a <em>Pair Account</em>
-                    panel will appear below this one — use it to associate
-                    the speaker with an account ID before presets and
-                    streaming work.
-                </p>
-
             </div>
 
             <!-- XML diff pair: Current Config | Planned Config. Shown