Refactor: investigate cleaner exception handling for server/server.cpp

[mofosyne]

Background Description

In #7642 @0wwafa observed unhanded exceptions on windows, but didn't provide a concrete example of a failure to load replications steps, so the root cause is unknown. He assert that every exception should be catched globally.

However @ngxson mentioned that we should do a more local try catch focused on ctx_server.init() as it makes no sense to cover ctx_server.load_model(params) which will always return false. 0wwafa opted afterwards to close the PR.

Considering that he did observe an exception around this area, we should at least give this spot a lookover to ensure all error cases are handled.

If done so, make sure to at least credit @0wwafa in the commit for the general observation.

Possible Refactor Approaches

• See if we can restrict the error handling to ctx_server.init() or closer to the error source.

[HanClinto]

Possibly related to #7391 as an extension / application of this -- in that case, the exception / error is being swallowed (not thrown), but it's still related to our overall approach of dealing with errors when in server mode (whether streaming or not).

[0wwafa]

Examples:

the simplest example is to run server.exe with a non existing model or wrong parameters.. the load fails (obviously) the exception is not caught and the program crashes.

[skoulik]

Also related: #7073, #7589