refactor of model targets and constraints, addition of new constraint types and constraint construction process

app/models/form.py

@@ -7,7 +7,8 @@ from typing import List, TypeVar, Type
 from helpers import irt_helper
 
 from models.item import Item
-from models.target import Target
+from models.targets.tif_target import TifTarget
+from models.targets.tcc_target import TccTarget
 
 from lib.irt.test_response_function import TestResponseFunction
 
@@ -19,8 +20,8 @@ _T = TypeVar("_T")
 class Form(BaseModel):
     items: List[Item]
     cut_score: float
-    tif_results: List[Target]
-    tcc_results: List[Target]
+    tif_results: List[TifTarget]
+    tcc_results: List[TccTarget]
     status: str = 'Not Optimized'
     solver_variables: List[str]