Switch from mcs to csc compiler with nostdlib

Use Roslyn compiler (csc) instead of old mcs to avoid netstandard 2.1 conflicts

build.sh

@@ -3,8 +3,14 @@
 # Set your 7DTD installation path
 GAME_DIR="${GAME_DIR:-$HOME/.local/share/7DaysToDie}"
 
-mcs -target:library \
+# Use csc (Roslyn compiler) instead of mcs
+csc -target:library \
     -out:BotCommandMod.dll \
+    -nostdlib \
+    -r:"$GAME_DIR/7DaysToDie_Data/Managed/mscorlib.dll" \
+    -r:"$GAME_DIR/7DaysToDie_Data/Managed/netstandard.dll" \
+    -r:"$GAME_DIR/7DaysToDie_Data/Managed/System.dll" \
+    -r:"$GAME_DIR/7DaysToDie_Data/Managed/System.Core.dll" \
     -r:"$GAME_DIR/7DaysToDie_Data/Managed/Assembly-CSharp.dll" \
     -r:"$GAME_DIR/7DaysToDie_Data/Managed/UnityEngine.CoreModule.dll" \
     -r:"$GAME_DIR/7DaysToDie_Data/Managed/0Harmony.dll" \