fix(ui): Admin password change didn't update the saved login copy

Tools > Admin > System > "Admin password" (set-only, sends "password
<new>") changes the remote node's own admin credential, but nothing
updated this device's saved copy of it -- so the very next login
attempt to that node retried the password just replaced, landing
straight in the "stuck on Logging in..." case fixed in the previous
commit. Likely the actual trigger behind that report.

CommonCLI::handleCommand() always echoes a successful password change
back as "password now: <value>" (truncation and all), so parsing that
reply gives the exact value now required to log back in, rather than
trusting what we sent (which the remote may have truncated further).

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

examples/companion_radio/ui-new/AdminScreen.h

@@ -410,6 +410,23 @@ public:
       openValueKb(trimmed);   // _pending_set_prefix is already set from activateField()
       return;
     }
+    // The "Admin password" row (SYSTEM_FIELDS, set-only) just changed the
+    // remote's own admin credential -- CommonCLI::handleCommand() always
+    // echoes it back as "password now: <value>" (see src/helpers/CommonCLI.cpp),
+    // truncation and all, so parsing that confirms the exact value now
+    // required to log back in. Without this, our saved password goes stale
+    // the instant this command succeeds, guaranteeing the next login attempt
+    // fails (see the LOGIN-phase timeout fix above for what that used to look
+    // like: a permanent "Logging in..." hang with a stale saved password).
+    static const char PW_ECHO_PREFIX[] = "password now: ";
+    if (!strncmp(text, PW_ECHO_PREFIX, sizeof(PW_ECHO_PREFIX) - 1)) {
+      char newpw[32];
+      strncpy(newpw, text + sizeof(PW_ECHO_PREFIX) - 1, sizeof(newpw) - 1);
+      newpw[sizeof(newpw) - 1] = '\0';
+      size_t n = strlen(newpw);
+      while (n > 0 && (newpw[n-1] == '\n' || newpw[n-1] == '\r' || newpw[n-1] == ' ')) newpw[--n] = '\0';
+      the_mesh.saveRoomPassword(_target.id.pub_key, newpw);
+    }
     strncpy(_reply_text, text, sizeof(_reply_text) - 1);
     _reply_text[sizeof(_reply_text) - 1] = '\0';
     _reply_view.begin();

release-notes.md

@@ -3,6 +3,7 @@
 ### Fixes
 
 - **Tools › Admin login could get stuck on "Logging in..." forever** if the remote node never sent back a reply — most commonly after its admin/room password was changed, since the on-device UI auto-retries the old saved password with no timeout to fall back on. It now gives up after the same estimated-timeout window the rest of Admin's commands use, forgets the stale saved password, and returns you to the picker to try again with the new one.
+- **Changing a remote's admin password from Tools › Admin › System didn't update this device's own saved copy** — the very next login attempt to that node retried the password you'd just replaced, hitting the "stuck on Logging in…" case above. The confirmation the remote echoes back is now saved as the new on-device password to match.
 
 ---