feat(assets): Add Texture Asset support (Task #18.0 prep)

- Integrated stb_image for image decompression in asset_packer.
- Added GetTextureAsset helper in asset_manager.
- Updated procedural asset generation to include dimensions header for consistency.
- Updated test_assets to verify new asset format.

1 files changed, 9 insertions, 0 deletions

diff --git a/src/util/asset_manager.h b/src/util/asset_manager.h
index 964b7af..7d332f2 100644
--- a/src/util/asset_manager.h
+++ b/src/util/asset_manager.h
@@ -32,3 +32,12 @@ struct AssetRecord {
 // - 'out_size' returns the original asset size (excluding the null terminator).
 const uint8_t* GetAsset(AssetId asset_id, size_t* out_size = nullptr);
 void DropAsset(AssetId asset_id, const uint8_t* asset);
+
+struct TextureAsset {
+  int width;
+  int height;
+  const uint8_t* pixels;
+};
+
+// Helper to retrieve and parse a simple texture asset (from packer's [w][h][pixels] format)
+TextureAsset GetTextureAsset(AssetId asset_id);