Stfaseid http refactor

Description

Draft for new API. Needs extensive manual testing. Only merge if changes in https://code.fbi.h-da.de/danet/api/-/tree/10-refactor-current-proto-definitions-stfahelm and upcoming changes to CLI are approved.

Related Issue

#141 (closed)

Motivation and Context

How Has This Been Tested?

Screenshots (if appropriate):

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.
• All new and existing tests passed.

northbound/server/core_test.go

@@ -57,7 +57,6 @@ func Test_core_Set(t *testing.T) {
 	}
 }
 
-//TODO faseid: update test!
 func Test_core_GetPnd(t *testing.T) {
 	type args struct {
 		ctx     context.Context