[Tarzelf]

Adds a local Godot workstation for the existing PiPER scene while keeping MuJoCo as the sole physics authority. The viewer sends bounded targets over localhost; each accepted command advances ten 2 ms physics ticks. Scene hashes, command ordering, reset behavior and timing remain explicit.

Includes the Godot project, a Python prepare/serve CLI, an independently replayable smoke receipt, and a staged roadmap for physical calibration and sim-to-real evaluation. This is a research prototype with an authored rigid shoe and solid-color geometry; it does not add learned skills, GLB/PBR import, physical calibration, or hardware control.

Validation:

• 19 focused Python tests and seven Godot coordinate assertions passed.
• 1,800 paired direct/bridge states matched exactly over 36,000 native ticks; CPU JSON-path throughput 49.71–50.15 simulated seconds per wall second, excluding sockets/rendering/learning.
• Actual windowed Godot smoke accepted 100 commands; independent replay checked 101 states/12,387 scalars, maximum error 5.11e-15.
• Latest paced viewer took 2.264 wall seconds for 2.00 simulated seconds. Earlier development timings and initial sandbox connection failure are retained and disclosed.
• Manual mouse/button interaction was not independently verified because native UI automation could not attach. Server reset and no-step keepalive behavior are unit-tested.

Stacked on the encoder-kinematics branch (PR #37). The existing workstation physics source and learned-skill qualification scores are unchanged.