Design a hyper-realistic 3D model of a Jack Russell Terrier that highlights its small, compact, and agile frame, perky ears, and lively, alert eyes. Render short, fine fur with intricate texture details and pose the dog in an energetic, playful stance. Include natural, high-contrast lighting to emphasize its spirited character. [Parameters: high-poly mesh, detailed textures, realistic dynamic lighting, rigged for motion].