Show linked filenames on exposure level page

[stscijgbot-jwql]

Issue JWQL-210 was created on JIRA by Bryan Hilbert:

From the JWQL user survey (NIRISS team):

When you are grouping by exposure rather than file/detector, show the hyperlinked filename in the jpeg preview page. Currently this is only shown on the file level page.

Maybe we need a new pull down menu for this? I'm thinking about cases with multiple detectors. Where on the page would we put a list of 10 filenames (for NIRCam), or 2 filenames (for NIRSpec).

PERHAPS A BETTER ISSUE: why do we have exposure level pages at all for instruments with only a single detector? In these cases, we should go straight from observation level to detector level.