Create UI: fix upload size labels (10 MB should be 30 MB)

In Create UI, there are 3 components that allow the upload of a file. The max file size was recently updated (from 10 MB to 30 MB), but the guidance text was not and is now incorrect, eg:


The following components need to be updated:
- [ ] Affidavit.vue
- [ ] UploadMemorandum.vue
- [ ] UploadRules.vue
- [ ] unit tests?

I recommend changing the hard-coded guidance text to a string computed using the MAX_FILE_SIZE variable in document-mixin.ts.

Locate Affidavit.vue, UploadMemorandum.vue, UploadRules.vue, and document-mixin.ts. Start by checking MAX_FILE_SIZE and the three upload guidance labels, then inspect the related unit tests if present. Done means all three components display guidance matching the 30 MB limit and the tests pass or are updated accordingly.

Written by the indexing model from the issue text.