chore(sync): mirror front-door files to Space (hf-sync)

feat(restraint): R2 front-end - 'Restraint applied' indicator on /nemo (rung+lines-saved+ceilings+signed receipt) and restraint verdict column on /agent-loop trace. Ponytail MIT, governed. Byte-identical to GitHub 3a8305e. Additive; PENDING until R1 live.

LANE A: resumable ReAct agentic core + Agent Loop/Memory/Skill Library UI (signed receipt boundaries, checkpoint/resume, Reflexion, Generative-Agents memory, Letta tiering, Voyager skills)