"if they wish to share it or accept job offers"
Sharing your resume through an external website might not require IAP but sharing it within the app certainly would require IAP, IMHO.
Accepting job offers could go either way. Again, 'through an external website' might not require IAP but doing it within the app raises the question of whether it is a 'real world service' or 'app content'. The job itself is real world and so you can't use IAP. But the acceptance of the job might be digital content and could be done through IAP.
Two paths - IAP and not-IAP. The IAP path requires that you seperate the 'accepting job offer' from the actual job. And that you allow Apple to handle all billing and send you a 70% share. The non-IAP requires that you do the sharing on an external website, perhaps viewed through the app, and that you link the acceptance of the job with an actual real world service. You may be able to share the resume within the app under 11.14.