feat: add game SDK and harden client login and game rules

- Add costume burst upgrades with durable replay and fix permanent SR equipment gacha.
- Add server game.json rules for optional collaboration UR weapons, with packaging and documentation.
- Add GameNames/GameSdk NuGet tooling, readable types, reobfuscation, complete source/PDB navigation and shared-runtime installation.
- Split plugin responsibilities, prefer typeof/nameof, centralize MSBuild settings and ignore local paths; remove the unused LoginUI test project.
- Fix login recovery and TLS through native platform HTTP and a private game relay; read device region directly from the OS time zone.

Validation: go test ./... -count=1, go vet ./..., plugin Release builds, SDK/runtime self-tests, Roslyn embedded-source navigation, gofmt check and git diff --check.

plugins/GameNames/GameMemberKind.cs

@@ -0,0 +1,14 @@
+namespace BD2.GameNames;
+
+/// <summary>Specifies the kind of game member whose readable name should be resolved.</summary>
+public enum GameMemberKind
+{
+    /// <summary>A method, including a coroutine entry point.</summary>
+    Method,
+    /// <summary>A field.</summary>
+    Field,
+    /// <summary>A property.</summary>
+    Property,
+    /// <summary>An event.</summary>
+    Event
+}