[MichalSzandar]

Sprite rendering

• New SpriteRenderer component, registered for the proto's renderer entry. It draws img_path stretched over the object's Transform, rotated clockwise about its centre.
• An empty img_path is allowed and draws nothing. An image path that can't be loaded fails the parse.
• When there is an image, the Transform must be finite, within float range, and have a positive width and height.
• If SDL fails to draw a sprite, the run stops before that frame is shown and before its marker is sent.

Image loading and upload

• New Image and ImageLibrary classes. Each scene loads each image file once while parsing, and sprites showing the same file share it.
• New onRenderTargetReady hook on components and the scene. The Renderer constructor calls it to upload images to the GPU before the first frame.
• Loaded images stay in memory, so textures are rebuilt after SDL_RENDER_DEVICE_RESET. The new Renderer::pollEvents() handles this, and Runtime also uses it while waiting for the EEG stream.
• Each texture keeps its SDL_Renderer alive.

Asset paths

• Every component creator now receives a ComponentBuildContext. Relative paths resolve against the folder holding the .neuroz; absolute paths are used as they are.
• Parser::parseStream(stream, assetRoot) takes the asset folder. The Blink and MarkerEmitter creators take the new parameter but don't use it.

Window

• The default window is created hidden, and Runtime shows it only after the scene is uploaded. A failed upload never shows a window to the participant.

Build and CI

• SDL2_image is a new dependency, added in CMake and in the CI packages.
• runtime_core now links the whole static library (runtime_core_archive). Otherwise the linker drops the code that registers components (REGISTER_COMPONENT).

Proto

• No net change: texture_path stays, and the runtime reads only img_path.

Tests

• New test files:
  • sprite_renderer_test
  • image_library_test
  • sprite_scene_test
  • component_build_context_test
  • temp_dir_test
  • registration_tests, a separate executable that checks every component is linked in
• New cases in RendererTest and runtime_test:
  • the render target reaching components
  • re-upload after a device reset
  • a failed draw sending no marker
  • the hidden window being shown
• Shared test helpers in tests/utils/: SdlTestUtils.hpp (software renderer, reading pixels, writing a PNG) and TempDir.hpp. Both existing test suites now use them instead of their own copies.

Docs

• README: component lifecycle and asset paths, the upload and window order, how registration works, and a Components status table with open questions.
• CLAUDE.md: a step for adding new components to registration_tests.

[Copilot]

Copilot was unable to review this pull request because the user who requested the review has reached their quota limit.

[Nowik11]

In my opinion there is no reason to change signature of proto file just to rename a field.

[Nowik11]

except from that lgtm

[Nowik11]

Lgtm