Session: bring back a taskbar saved on a screen the desktop doesn't have

Plasma 6.2.5 keeps a panel on a screen number and never moves one whose
number is past the screen count, so a taskbar saved on a spare output
(#18, lastScreen=8 with three screens) or on a screen a smaller layout
dropped stayed hidden. Before Plasma starts, session/fix-panels.py moves
such a panel and its tray's containment to screen 0 (the primary),
keeping its widgets, unless screen 0 already has a panel on that edge.
doctor.sh checks the panels' screens, and report.sh lists them with the
live outputs and panels.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

session/frametop-session.sh

@@ -272,4 +272,9 @@ fi
 # with both, apps would open twice.
 kwriteconfig6 --file "$XDG_CONFIG_HOME/ksmserverrc" --group General --key loginMode emptySession
 
+# Plasma keeps a panel on a screen number, and never moves one whose screen this desktop
+# doesn't have, like a spare output or a screen a smaller layout dropped. Put such a panel
+# back on the first (primary) screen before Plasma reads the file (session/fix-panels.py).
+python3 "$here/fix-panels.py" --screens "$screens" || true
+
 dbus-run-session startplasma-wayland