nas: 4 new CLI commands + --group on model list (G4)

[probicheaux]

Description

Wraps the new public API routes from the agentic-surface-area onsite plan as CLI commands. Companion backend PRs:

• roboflow#11603 — G1, validator
• roboflow#11605 — G6, projection + ?group=
• roboflow#11610 — G2, public train cancel/stop + favorite
• roboflow#11612 — G3, training results
• roboflow-mcp#34 — sister G5 (MCP)

New CLI commands

roboflow train cancel <project>/<version> [--continue-if-no-refund]
roboflow train stop   <project>/<version>
roboflow train results <project>/<version>
roboflow model star   <model-id> [--unstar]

Plus roboflow model list -p <project> -g/--group <modelGroup> — the canonical "list NAS models per run" path. When --group is set, the list command hits the public /models endpoint with the enriched projection (hardware/latency/map5095/paretoOptimalFor/recommended) instead of walking versions via the SDK.

Adapter additions

In roboflow/adapters/rfapi.py:

• cancel_version_training, stop_version_training
• get_training_results
• list_project_models (with optional group=), get_model_by_url
• favorite_nas_model

Tests

+13 cases across test_train_handler.py and test_model_handler.py covering register, happy paths, the 409/CANNOT_CANCEL hint surfacing, the MODEL_NOT_NAS hint, the unstar flow, and the --group endpoint switch. 298/298 CLI tests pass locally; ruff check + ruff format clean.

CLI-COMMANDS.md got two new sections — Train, monitor, cancel, stop and NAS models — list, star, deploy.

E2E

Driven against staging (api.roboflow.one) on peter-robicheaux/beer-can-hackathon:

$ roboflow --json train results peter-robicheaux/beer-can-hackathon/410
  jobType: nas, modelGroup: pVYKOWUB6AUIVJMgPc7u-410-rfdetrNasGroup,
  modelCount: 52, recommendedByHardware: {gpu: ...}, mining bundle present

$ roboflow model list -p peter-robicheaux/beer-can-hackathon -g pVYKOWUB6AUIVJMgPc7u-410-rfdetrNasGroup
  53-row leaderboard table with HARDWARE / LATENCY / MAP50 / MAP5095 / REC columns

$ roboflow --json -w peter-robicheaux model star 14CwSGmGetWh6rB0EnjL
  {"success": true, ...}    ← real NAS child id from train results
$ roboflow --json -w peter-robicheaux model star 14CwSGmGetWh6rB0EnjL --unstar
  {"success": true, ...}    ← favorites map flips

$ roboflow --json train cancel peter-robicheaux/beer-can-hackathon/318
  {"error": {"message": "...", "hint": "Cancel only applies to in-flight runs..."}}
  ← 409 from server surfaces with actionable hint

E2E exposed one error-shape mismatch on the backend (flat {error: "Conflict", message: ...} lost the descriptive message through the CLI's parser); fixed in roboflow#11610 (nested {error: {message, code, type}}).

How tested

python -m pytest tests/cli/ (298 passing) + manual roboflow ... invocations against staging.