Enable Ministry to Mandate new Monthly Disbursement Schedule for Specific Schools

**User Story**
As a student attending particular schools with reputation for claiming entire award amounts as remittance, I want the ability for Ministry to set unique disbursement schedule for myself and any other students attending my school so that I am more likely to retain my award amounts and be able to cover my expenses without all money being lost to remittance.

**Description**
Enable Ministry user to specify a monthly disbursement schedule for an entire school.

Acceptance Criteria
- [ ] Introduce new disbursement schedule in disbursement workflow. This would allow payload to be divided equally across every month of the student's studies.
- [ ] Enable Ministry to apply this unique disbursement schedule for particular schools such that every student attending those schools will be subject to monthly disbursements

Start by locating the disbursement workflow and the existing schedule handling. Trace how student and school data are used there, then determine where a school-specific monthly schedule belongs. Done means the workflow can divide an award across the student's study months and Ministry users can apply that schedule to a school.

Written by the indexing model from the issue text.