Fix WMO wall collision, normal mapping, POM backfill, and M2/WMO rendering performance

- Fix MOPY flag check (0x08 not 0x01) for proper wall collision detection
- Cap MAX_PUSH to PLAYER_RADIUS to prevent gradual clip-through
- Fix WMO doodad quaternion component ordering (X/Y swap)
- Linear normal map strength blend in shader for smooth slider control
- Enable shadow sampling for interior WMO groups (covered outdoor areas)
- Backfill deferred normal/height maps after streaming with descriptor rebind
- M2: prepareRender only iterates animated instances, bone dirty flag
- M2: remove worker thread VMA allocation, skip unready bone instances
- WMO: persistent visibility vectors, sequential culling
- Add FSR EASU/RCAS shaders

include/rendering/character_renderer.hpp

@@ -66,6 +66,8 @@ public:
 
     void update(float deltaTime, const glm::vec3& cameraPos = glm::vec3(0.0f));
 
+    /** Pre-allocate GPU resources (bone SSBOs, descriptors) on main thread before parallel render. */
+    void prepareRender(uint32_t frameIndex);
     void render(VkCommandBuffer cmd, VkDescriptorSet perFrameSet, const Camera& camera);
     void recreatePipelines();
     bool initializeShadow(VkRenderPass shadowRenderPass);