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>

Assets/_Project/Scripts/Simulation/Player/PlayerAimSystem.cs

@@ -22,7 +22,7 @@ namespace ProjectM.Simulation
         {
             foreach (var (facing, transform, input) in
                      SystemAPI.Query<RefRW<PlayerFacing>, RefRW<LocalTransform>, RefRO<PlayerInput>>()
-                         .WithAll<Simulate>())
+                         .WithAll<Simulate>().WithDisabled<Dead>())
             {
                 float2 aim = input.ValueRO.Aim;
                 if (math.lengthsq(aim) < 1e-6f)