"Inactive" notes not exported

I exported my notes via the web app as a backup. When I looked inside the zip file, I found that not all my notes were included. Only about half of them were present.

In the `notes.json` file, I found two keys: `activeNotes`, with about as many members as there were notes in the zip file directory, and `trashedNotes`, listing all deleted notes.

So I'm guessing that when Simplenote exports notes, it exports only what it considers "active" notes (that is, I'm also guessing, notes that have been updated recently). By inspection, the cutoff date seems to be about five years ago.

I would have expected that the 'Export notes' feature would export all notes, but it doesn't. My backup file is missing many important old notes. Interestingly, _trashed_ notes seem to be included no matter how old they are. This doesn't quite make sense from the user's point of view, since notes that have been deleted are less important to retain than notes that haven't.

How can I export _all_ notes, including "inactive" ones?

Start at the web app's "Export notes" entry point and inspect how notes.json is generated inside the export zip. Reproduce the export with old, active, and trashed notes, then verify that the completed backup includes all non-deleted notes regardless of age.

Written by the indexing model from the issue text.