When the principle that building a sense of accomplishment by solving problems within one's own capacity strengthens one's moral self conflicts with the principle that pursuing affirmation of existence without firm attachment risks being blindly reinforced, which principle should take priority?

The kind of decision situation where those principles conflict is probably one where the person has neither a secure attachment nor a sturdy sense of self-efficacy. In that case, I would first recommend restoring self-efficacy. After all, that situation presupposes external intervention, and restoring self-efficacy can be carried out at a relatively low supervision cost, such as assigning work or games, whereas providing secure attachment is a very difficult condition to meet. So I would choose the direction of first restoring self-efficacy so that the person becomes a sound member of society, and then providing a solution for forming attachment at that point.

However, if AI becomes highly developed and a solution emerges that can provide an individual with absolute emotional support, I would be willing to recommend the former first.