Import art/VFX asset packs + game-feel systems; normalize texture extensions to lowercase for LFS

Add BefourStudios SciFi environment packs, Gabriel Aguiar VFX, and the
ShaderCrew Toon Shader embedded packages, plus combat/enemy/wave/death
gameplay systems and supporting vault docs/screenshots.

Rename 11 vendor textures from uppercase .PNG/.HDR to lowercase so the
case-sensitive Git LFS filters (*.png/*.hdr) match on case-sensitive
filesystems (Linux CI, case-sensitive macOS), not just locally where
core.ignorecase=true masks the gap. Each .meta moved with its asset so
GUID references are preserved. All ~1000 binaries tracked via LFS.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Packages/com.shadercrew.the-toon-shader.3d/Scripts/Runtime/Demo/RPHelperToonSTS.cs

@@ -0,0 +1,22 @@
+using System.Collections;
+using System.Collections.Generic;
+using UnityEngine;
+
+namespace ShaderCrew.TheToonShader
+{
+    [AddComponentMenu(Strings.COMPONENTMENU_RPHELPER)]
+    public class RPHelperToonSTS : MonoBehaviour
+    {
+        // Start is called before the first frame update
+        void Start()
+        {
+
+        }
+
+        // Update is called once per frame
+        void Update()
+        {
+
+        }
+    }
+}