System Announcements - UI - Pages, Dashboards, and Forms 2/3 (Create)

As a Ministry user, I need to be able to publish banners on the various SIMS sites for different users, to notify about system changes or outages. These can be shown prior to users being authenticated on the login pages for Supporting Users, Students, and Institutions. They can also be shown to authenticated users after login: Institutions, Ministry, Students (not Supporting users). This announcement will be on the page on login (Home), it is not dismissible, but does not follow the user as they navigate. There can be multiple announcements within the same banner for each portal.

See also #3172 and #3174. Examples of announcements in the epic.

## **Acceptance Criteria**

### Create Page
- [ ] Create System Announcement form has 6 fields:
- Name _(required, not unique, 100 chars)_
- Portal _(minimum one required, can select all)_
- Start Date _(required, enforce today's date or future date)_
- Message _(required, max 250 chars)_ Please include simple formatting options like bold/italics and hyperlinks. (not shown in mock-up, please add/enable)._
- [ ] 5 different ~~portals~~ **Display Location(s)** that banners can be shown in:
- authenticated institution ~~portal~~ - "Institution"
- unauthenticated institution ~~portal~~ - "Institution (Login Page)"
- authenticated ministry ~~portal~~ - "Ministry"
- authenticated student ~~portal~~ - "Student"
- unauthenticated student ~~portal~~ - "Student (Login Page)"
- unauthenticated supporting user ~~portal~~ - "Supporting User (Login Page)"
- [ ] notification banner statuses:
- Active (start date today or in the past)
- Scheduled (future start date)
- Inactive (has been deactivated)

_Fig 1:_

No files, tests, or entry points are named in the issue. Read related issues #3172 and #3174 and the epic examples first, then use the Create Page acceptance criteria to define the form fields, display locations, formatting, date rules, and status behavior that must be complete.

Written by the indexing model from the issue text.