Update SA-5 Generator for factions without the TinShield

- added an EarlySA5Generator with the P-19 FlatFace SR which is supported by all factions
- allows factions without access to the TinShield to have a working SA-5

cherry-pick from f526681f

gen/sam/sam_sa5.py

@@ -1,5 +1,10 @@
+from typing import Type
+
+from dcs.unittype import VehicleType
 from dcs.vehicles import AirDefence, Unarmed
 
+from game import Game
+from game.theater import SamGroundObject
 from gen.sam.airdefensegroupgenerator import (
     AirDefenseRange,
     AirDefenseGroupGenerator,
@@ -8,15 +13,18 @@ from gen.sam.airdefensegroupgenerator import (
 
 class SA5Generator(AirDefenseGroupGenerator):
     """
-    This generate a SA-5 group
+    This generate a SA-5 group using the TinShield SR
     """
 
     name = "SA-5/S-200 Site"
 
-    def generate(self) -> None:
+    def __init__(self, game: Game, ground_object: SamGroundObject):
+        super().__init__(game, ground_object)
+        self.sr: Type[VehicleType] = AirDefence.RLS_19J6
 
+    def generate(self) -> None:
         self.add_unit(
-            AirDefence.RLS_19J6,
+            self.sr,
             "SR",
             self.position.x,
             self.position.y,
@@ -54,3 +62,14 @@ class SA5Generator(AirDefenseGroupGenerator):
     @classmethod
     def range(cls) -> AirDefenseRange:
         return AirDefenseRange.Long
+
+
+# TODO Replace this legacy handling once the Generators can be faction sensitive #1903
+class SA5FlatFaceGenerator(SA5Generator):
+    """
+    This generate a SA-5 group using the P-19 FlatFace SR
+    """
+
+    def __init__(self, game: Game, ground_object: SamGroundObject):
+        super().__init__(game, ground_object)
+        self.sr: Type[VehicleType] = AirDefence.P_19_s_125_sr