Update test fixtures to current runtime contracts (#14259)

Recent runtime changes left the aggregate suite expecting a VS Code symlink and fixed extension version, pacman arguments without the end-of-options marker, a one-argument QML text signal, and background functions without preparation state. Align these fixtures with the current interfaces while retaining palette equality, package retry, keyboard action, and missing-background recovery assertions.

Co-authored-by: Omarchybot <317366263+omarchybot@users.noreply.github.com>

test/shell.d/omarchy-kernel-migration-test.sh

@@ -22,7 +22,7 @@ boot_order='BOOT_ORDER="linux-omarchy, linux-omarchy-*, *, *fallback, Snapshots"
 cat > "$scratch/bin/pacman" <<'SH'
 #!/bin/bash
 case "$1" in
-  -Q) grep -Fxq "$2" "$INSTALLED_PACKAGES" ;;
+  -Q) [[ $2 == -- ]] || exit 99; grep -Fxq -- "$3" "$INSTALLED_PACKAGES" ;;
   -S)
     printf 'pacman %s\n' "$*" >> "$CALL_LOG"
     [[ ${INSTALL_FAIL:-0} == "0" ]] || exit 1
@@ -154,7 +154,7 @@ for name in dell-xps-panther-lake zz-dell-xps-panther-lake; do
 done
 cp "$OMARCHY_KERNEL_LIMINE_CONF" "$OMARCHY_KERNEL_LIMINE_DROP_INS/omarchy-defaults.conf"
 run_migration
-grep -Fxq "pacman -S --noconfirm --needed $kernel $kernel-headers" "$CALL_LOG" || fail "both new packages are installed"
+grep -Fxq "pacman -S --noconfirm --needed -- $kernel $kernel-headers" "$CALL_LOG" || fail "both new packages are installed"
 grep -Fxq linux-ptl "$INSTALLED_PACKAGES" || fail "the old kernel is kept for recovery"
 grep -Fxq linux-ptl-headers "$INSTALLED_PACKAGES" || fail "the old kernel headers are kept"
 assert_preferred "$OMARCHY_KERNEL_LIMINE_CONF"