Is the wife justified in requesting her husband to provide stable accommodation for her and their child before he travels for jihad, or does this indicate her weak faith and attachment to worldly life?

Among the wife's rights upon her husband is the provision of an independent dwelling for her. It is not a condition that it be owned by the husband; rather, it is sufficient for him to possess its usufruct through rent or loan. As for the wife traveling with her husband to Syria, obedience is not obligatory in this matter if the route or the place is unsafe. Your demand for housing and your fear of travel do not contradict reliance on Allah, for certainty does not negate taking permissible means.