Add decorative civilian buildings to random maps

Allows the random map generator to optionally place civilian buildings
around the map for extra decoration. Buildings are placed last with
lowest priority to avoid competing for play area and resources.

Depends on #21738

mods/ra/tilesets/desert.yaml

@@ -4166,3 +4166,48 @@ MultiBrushCollections:
 			Actor: tc01.husk
 			BackingTile: 255,0
 			Weight: 100
+	CivilianBuildings:
+		MultiBrush@v20:
+			Actor: v20
+			Weight: 25000
+		MultiBrush@v21:
+			Actor: v21
+			Weight: 25000
+		MultiBrush@v22:
+			Actor: v22
+			Weight: 10000
+		MultiBrush@v23:
+			Actor: v23
+		MultiBrush@v24:
+			Actor: v24
+			Weight: 25000
+		MultiBrush@v25:
+			Actor: v25
+			Weight: 25000
+		MultiBrush@v26:
+			Actor: v26
+			Weight: 10000
+		MultiBrush@v27:
+			Actor: v27
+		MultiBrush@v28:
+			Actor: v28
+		MultiBrush@v29:
+			Actor: v29
+		MultiBrush@v30:
+			Actor: v30
+			Weight: 10000
+		MultiBrush@v31:
+			Actor: v31
+			Weight: 10000
+		MultiBrush@v32:
+			Actor: v32
+			Weight: 10000
+		MultiBrush@v33:
+			Actor: v33
+			Weight: 10000
+		MultiBrush@v34:
+			Actor: v34
+		MultiBrush@v35:
+			Actor: v35
+		MultiBrush@v36:
+			Actor: v36

mods/ra/tilesets/snow.yaml

@@ -4351,3 +4351,51 @@ MultiBrushCollections:
 			Actor: t17
 			BackingTile: 255,0
 			Weight: 100
+	CivilianBuildings:
+		MultiBrush@v01:
+			Actor: v01
+			Weight: 25000
+		MultiBrush@v02:
+			Actor: v02
+			Weight: 25000
+		MultiBrush@v03:
+			Actor: v03
+			Weight: 25000
+		MultiBrush@v04:
+			Actor: v04
+			Weight: 25000
+		MultiBrush@v05:
+			Actor: v05
+			Weight: 10000
+		MultiBrush@v06:
+			Actor: v06
+			Weight: 10000
+		MultiBrush@v07:
+			Actor: v07
+			Weight: 10000
+		MultiBrush@v08:
+			Actor: v08
+		MultiBrush@v09:
+			Actor: v09
+		MultiBrush@v10:
+			Actor: v10
+		MultiBrush@v11:
+			Actor: v11
+		MultiBrush@v12:
+			Actor: v12
+		MultiBrush@v13:
+			Actor: v13
+		MultiBrush@v14:
+			Actor: v14
+		MultiBrush@v15:
+			Actor: v15
+		MultiBrush@v16:
+			Actor: v16
+		MultiBrush@v17:
+			Actor: v17
+		MultiBrush@v18:
+			Actor: v18
+		MultiBrush@railmine:
+			Actor: railmine
+		MultiBrush@snowhut:
+			Actor: snowhut

mods/ra/tilesets/temperat.yaml

@@ -4838,3 +4838,53 @@ MultiBrushCollections:
 		MultiBrush@588:
 			Template: 588
 			Weight: 100
+	CivilianBuildings:
+		MultiBrush@v01:
+			Actor: v01
+			Weight: 25000
+		MultiBrush@v02:
+			Actor: v02
+			Weight: 25000
+		MultiBrush@v03:
+			Actor: v03
+			Weight: 25000
+		MultiBrush@v04:
+			Actor: v04
+			Weight: 25000
+		MultiBrush@v05:
+			Actor: v05
+			Weight: 10000
+		MultiBrush@v06:
+			Actor: v06
+			Weight: 10000
+		MultiBrush@v07:
+			Actor: v07
+			Weight: 10000
+		MultiBrush@v08:
+			Actor: v08
+		MultiBrush@v09:
+			Actor: v09
+		MultiBrush@v10:
+			Actor: v10
+		MultiBrush@v11:
+			Actor: v11
+		MultiBrush@v12:
+			Actor: v12
+		MultiBrush@v13:
+			Actor: v13
+		MultiBrush@v14:
+			Actor: v14
+		MultiBrush@v15:
+			Actor: v15
+		MultiBrush@v16:
+			Actor: v16
+		MultiBrush@v17:
+			Actor: v17
+		MultiBrush@v18:
+			Actor: v18
+		MultiBrush@railmine:
+			Actor: railmine
+		MultiBrush@rice:
+			Actor: rice
+		MultiBrush@asianhut:
+			Actor: asianhut