docs: update all docs for publication

- README.md: new — features, quick start, controls, MCP tools, requirements
- AGENTS.md: rewritten for pure P/Invoke Vulkan 1.3 (was Raylib/OpenGL)
- CORTEX_ENGINE_ARCHITECTURE.md: complete rewrite — current architecture,
  frame loop, UBO layout, push constants, shadow mapping, PBR, AI/MCP,
  physics, ImGui, video recording, content, testing
- VULKAN_IMPLEMENTATION_PLAN.md: marked as COMPLETE with all 21 phases
- scripts/run.sh: updated examples
- .gitignore: added Videos/, imgui.ini, cortex.mp4
- Removed tracked imgui.ini and video files

README.md

@@ -0,0 +1,75 @@
+# Cortex Engine
+
+AI-Native 3D game engine with pure P/Invoke Vulkan 1.3 render backend.
+
+## Features
+
+- **Vulkan 1.3** — dynamic rendering, synchronization2, pure P/Invoke (no wrapper libraries)
+- **PBR Shading** — Cook-Torrance BRDF, ACES tonemapping, multi-light support
+- **Cubemap Array Shadows** — omnidirectional shadows from multiple point lights, 16-tap Poisson disk PCF
+- **Jolt Physics** — rigid body dynamics, box/sphere colliders, gravity
+- **ImGui** — debug overlay, light/shadow/physics controls
+- **AI/MCP** — 7 tools (spawn, transform, material, delete, list, world state, screenshot) via HTTP/SSE
+- **Video Recording** — FFmpeg pipe, 60 FPS capture, 30 FPS output
+- **ECS** — Flecs.NET with Transform, Mesh, Material, Light, Camera, RigidBody components
+- **SDL3 Window** — cross-platform, Vulkan surface
+
+## Quick Start
+
+```bash
+# Build
+dotnet build CORTEX_ENGINE.sln -c Debug
+
+# Run
+./scripts/run.sh
+
+# Run with AI/MCP server
+./scripts/run.sh -- --mcp-port 5000
+
+# Run tests
+dotnet test tests/Engine.Tests/Engine.Tests.csproj -c Debug
+```
+
+## Controls
+
+- **WASD** — move camera
+- **Right-click + drag** — look around
+- **Q/E** — down/up
+- **Shift** — speed boost
+- **ESC** — quit
+
+## ImGui Panels
+
+- **Cortex Engine Debug** — FPS, camera, entity count, physics toggle, reset scene
+- **Shadow & Light Parameters** — per-light intensity/range/RGB, shadow bias/radius/farplane, ambient RGB
+- **Video Recording** — start/stop recording to MP4
+
+## MCP Tools
+
+Connect via `http://localhost:5000/` (SSE):
+
+| Tool | Description |
+|---|---|
+| `spawn_model` | Create object (cube/sphere, optional physics) |
+| `set_transform` | Move/rotate/scale by name |
+| `set_material` | Change color/roughness/metallic |
+| `delete_entity` | Remove object |
+| `list_entities` | List all objects |
+| `get_world_state` | Full JSON state |
+| `capture_screenshot` | Request screenshot |
+
+## Requirements
+
+- .NET 9 SDK
+- Vulkan 1.3+ drivers
+- SDL3 (bundled via NuGet)
+- FFmpeg (for video recording)
+- glslangValidator (for shader recompilation)
+
+## Architecture
+
+See [CORTEX_ENGINE_ARCHITECTURE.md](CORTEX_ENGINE_ARCHITECTURE.md) for full technical docs.
+
+## License
+
+All rights reserved.