you cannot detect the end user's domain account directly.

maybe you could loosely infer it.

because your application is using a "common" login, only the application knows who it is;

if you can modify the application, you can start adding a log or something to capture this information.

you'll see a lot of people might modify their application to also echo the domain account into updates to CreatedBy or UpdatedBy columns.

to loosely infer it, you can use powershell to get a list of all computers, and the last person to login to that computer, and stuff that into a table for reference....since most people only use a single machine at their job, finding computer/user pairs lets you infer that Dev223=mydomian\Lowell, which is a pretty good approximation of the actual user.

then , hopefully, the application is passing the hostname to the connection string, so you could join hostname to computer name, and infer the user.

I've used this exact method to detect when a sql user was used by a developer to connect in a server login trigger