Add version 1.0.5 and /api/version endpoint

- Added Version, AssemblyVersion, and FileVersion to project file
- Added /api/version endpoint returning version info
- Follows SilverPay versioning pattern

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

LittleShop/LittleShop.csproj

@@ -5,6 +5,9 @@
     <Nullable>enable</Nullable>
     <ImplicitUsings>enable</ImplicitUsings>
     <UserSecretsId>b96bedcb-5d39-4d41-98c0-72355dd49c1b</UserSecretsId>
+    <Version>1.0.5</Version>
+    <AssemblyVersion>1.0.5.0</AssemblyVersion>
+    <FileVersion>1.0.5.0</FileVersion>
   </PropertyGroup>
 
   <ItemGroup>