feat(fsharp): m01-m06 util, model, rules, random, spawn, game, view with Expecto tests

Co-Authored-By: Claude Opus 5.5 <[email protected]>

fsharp/solutions/Snake.fsproj

@@ -1,9 +1,17 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
     <TargetFramework>net10.0</TargetFramework>
+    <!-- FS0046: `pure` is reserved for future use by F#; the course keeps the name used by every track. -->
+    <NoWarn>$(NoWarn);FS0046</NoWarn>
     <TreatWarningsAsErrors>false</TreatWarningsAsErrors>
   </PropertyGroup>
   <ItemGroup>
     <Compile Include="Util.fs" />
+    <Compile Include="Model.fs" />
+    <Compile Include="Rules.fs" />
+    <Compile Include="Random.fs" />
+    <Compile Include="Spawn.fs" />
+    <Compile Include="Game.fs" />
+    <Compile Include="View.fs" />
   </ItemGroup>
 </Project>