Improve AI strike targeting.

We were setting up all the correct *target* waypoints but the AI doesn't
use the target waypoints; they use the targets property of the ingress
waypoint. This meant that the flight plan looked correct in the UI and
was correct for players but the tasks were set up incorrectly for the AI
because building TGOs are aggravatingly multiple TGOs with the same name
in the implementation.

Mission targets now enumerate their own strike targets so that this
mistake is harder to make in the future.

This won't be perfect, the AI is still not able to parallelize tasks and
since buildings aren't groups they can only attack one structure at a
time, but they'll now at least switch to the next target after hitting
the first one.

As a bonus, stop bombing the dead buildings.

Fixes https://github.com/dcs-liberation/dcs_liberation/issues/235
Fixes https://github.com/dcs-liberation/dcs_liberation/issues/244

gen/kneeboard.py

@@ -26,7 +26,7 @@ import datetime
 from collections import defaultdict
 from dataclasses import dataclass
 from pathlib import Path
-from typing import Dict, List, Optional, TYPE_CHECKING, Tuple
+from typing import Dict, List, Optional, TYPE_CHECKING, Tuple, Iterator
 
 from PIL import Image, ImageDraw, ImageFont
 from dcs.mission import Mission
@@ -38,7 +38,7 @@ from game.utils import meters
 from .aircraft import AIRCRAFT_DATA, FlightData
 from .airsupportgen import AwacsInfo, TankerInfo
 from .briefinggen import CommInfo, JtacInfo, MissionInfoGenerator
-from .flights.flight import FlightWaypoint, FlightWaypointType
+from .flights.flight import FlightWaypoint, FlightWaypointType, FlightType
 from .radios import RadioFrequency
 from .runways import RunwayData