Create "Crew Definition" page for map dashboard

this is for use by the crew themselves, or by crew ops

1. assigns individual radios to named crew members (note that this can be overwritten by the "EVA Definition" page)
2. sets crew start and end dates
3. captures name / number of crew
4. flag (default value = "No") if they opt out of recording EVA audio (any other privacy-related settings needed?)

Store the above for each crew in the database. Make these attributes available for searching, and when doing things like searching for "my EVA's" or "Crew 301's EVA's"

The payload names the map dashboard and the existing EVA Definition page, but no files or tests. Start by locating those entry points and tracing how crew data is stored and searched. Done means the page captures the listed crew and radio attributes, persists them, supports searching, and resolves how privacy-related settings interact with EVA Definition.

Written by the indexing model from the issue text.