Initial commit: Theriapolis baseline at port/godot branch point

Captures the pre-Godot-port state of the codebase. This is the rollback
anchor for the Godot port (M0 of theriapolis-rpg-implementation-plan-godot-port.md).
All Phase 0 through Phase 6.5 work is included; Phase 7 is in flight.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

Theriapolis.Game/Rendering/IMapView.cs

@@ -0,0 +1,13 @@
+using Microsoft.Xna.Framework;
+using Microsoft.Xna.Framework.Graphics;
+
+namespace Theriapolis.Game.Rendering;
+
+/// <summary>
+/// Common interface for world-map and tactical renderers.
+/// Both share the same Camera2D and render the same polyline data.
+/// </summary>
+public interface IMapView
+{
+    void Draw(SpriteBatch spriteBatch, Camera2D camera, GameTime gameTime);
+}