feat: initial datamodel + ef connection and migrations

Initial version of the data model
Includes EF initialization and migrations
EF migrations are applied on application start

TournamentOrganizer.Browser/wwwroot/main.js

@@ -0,0 +1,13 @@
+import { dotnet } from './_framework/dotnet.js'
+
+const is_browser = typeof window != "undefined";
+if (!is_browser) throw new Error(`Expected to be running in a browser`);
+
+const dotnetRuntime = await dotnet
+    .withDiagnosticTracing(false)
+    .withApplicationArgumentsFromQuery()
+    .create();
+
+const config = dotnetRuntime.getConfig();
+
+await dotnetRuntime.runMain(config.mainAssemblyName, [globalThis.location.href]);