Is it permissible to help repair the dwelling of a non-working divorced woman who uses drugs—by connecting water, repairing the bathroom, and paying workers' wages—given that she promised to quit drugs and has no one to support her?

There is no harm in helping a disobedient person from zakat (definition) or voluntary charity, such as repairing a house or similar things, as long as it does not aid in disobedience. This charity may be a cause for their guidance, for giving charity to a wicked person or a disbeliever is permissible, and the giver is rewarded for it. It is recommended to utilize this charity to advise the disobedient person and remind them of God, and to help them find a job that will relieve them of need.