feat: check type in return of `resolveShader`

[Daniel Báez]

    function resolveShader(
        src: RenderProps["shader"],
    ): ShaderData | Asset<ShaderData> | null {
        if (!src) {
            return gfx.defShader;
        }
        if (typeof src === "string") {
            const shader = getShader(src);
            if (shader) {
                return shader.data ?? shader;
            } else if (loadProgress() < 1) {
                return null;
            } else {
                throw new Error(`Shader not found: ${src}`);
            }
        } else if (src instanceof Asset) {
            return src.data ? src.data : src;
        }
        // TODO: check type
        // @ts-ignore
        return src;
    }

[Daniel Báez]

To do it I have to remove type duplication between types.ts and other modules, also rework in declaration files generation