feat(gen-sim): add task contracts and scene authoring boundary

[skywhite1024]

Stack

• Layer: 1/6
• Base: main
• Depends on: none
• Followed by: feat(task-engine): add semantic task frontend #534

Description

This PR establishes the cross-engine foundation for the rebuilt GenSim stack. It adds the scene-independent Task Engine contracts and ontology, structured instruction validation, and the narrow Scene Engine analyze/materialize authoring boundary still required after the mainline Scene Engine updates.

It supersedes the remaining non-mainline contract surface from #532 without carrying the duplicated Scene Engine implementation.

Type of change

• Bug fix
• Enhancement
• New feature
• Breaking change
• Documentation update

Validation

• black --check --diff --color ./
• python docs/scripts/check_api_docs.py
• pytest tests/gen_sim/scene_engine/test_pipeline_api.py tests/gen_sim/task_engine/test_interpretation.py -q (6 passed)

Checklist

• Code is formatted with Black 26.3.1
• Public API documentation is aligned
• Focused tests cover the new contracts and authoring boundary
• This layer is independently importable and testable

[greptile-apps]

Greptile Summary

This PR introduces the Action Engine's SeedGraph contracts, semantic and atomic capability registries, runtime policy configuration, motion/orientation contracts, and task ontology.

• Adds strict validation and hashing for task specifications, SeedGraphs, execution programs, and action contracts.
• Adds deterministic semantic-operator expansion and atomic capability metadata.
• Adds versioned runtime-policy defaults, migration paths, and typed motion modifiers.
• Adds focused tests for runtime policy, task contracts, and motion policy.

Confidence Score: 4/5

The profile normalization defect should be fixed before merging because supported snapshot-less and legacy agent configurations can fail during policy loading.

Agent runtime-policy loading bypasses the singular-to-dual profile aliases used elsewhere, so the package's own ur10 default is rejected by fallback and legacy migration paths.

Files Needing Attention: embodichain/gen_sim/action_engine/config/runtime_policy.py

Important Files Changed

Filename	Overview
embodichain/gen_sim/action_engine/config/runtime_policy.py	Adds strict runtime-policy loading and migrations, but agent loading fails for supported singular robot profile names on fallback and legacy paths.
embodichain/gen_sim/action_engine/domain/v2.py	Adds comprehensive SeedGraph v3 validation for topology, contracts, ownership transitions, cleanup barriers, and resource conflicts.
embodichain/gen_sim/action_engine/capabilities/atomic.py	Defines atomic capability metadata and serializable state/resource contracts; no independently publishable defect was established on a current caller path.
embodichain/gen_sim/action_engine/capabilities/builtins.py	Adds semantic operator expansion and phase templates for placement, arrangement, orientation, and coordinated transport.
embodichain/gen_sim/action_engine/domain/programs.py	Adds strict coordinate-free TaskAgent and ExecutionProgram validation and hashing.
embodichain/gen_sim/task_engine/ontology.py	Adds the canonical task ontology consumed by the new Action Engine task contracts.

Flowchart

%%{init: {'theme': 'neutral'}}%%
flowchart LR
  TS[Task specification] --> OP[Semantic operator expansion]
  OP --> SG[SeedGraph with action contracts]
  SG --> VP[SeedGraph validation]
  VP --> EP[Execution program]
  RP[Runtime policy snapshot] --> MR[Motion policy resolution]
  EP --> MR
  MR --> AA[Atomic action execution]

Loading

Prompt To Fix All With AI

### Issue 1
embodichain/gen_sim/action_engine/config/runtime_policy.py:623-625
**Profile aliases bypassed during loading**

When a snapshot-less or legacy agent uses a supported singular profile such as `ur10`, `ur5`, `ur3`, or `franka`, `resolve_agent_runtime_policy` forwards it without the alias normalization used by motion-policy resolution, causing `default_runtime_policy` to raise `ValueError` instead of loading the corresponding `dual_*` defaults.

---

For each issue above, determine whether it is valid and should be fixed. If so, fix it directly.

_{Reviews (1): Last reviewed commit: "feat(action-engine): add SeedGraph contr..." | Re-trigger Greptile}

[greptile-apps]

Profile aliases bypassed during loading

When a snapshot-less or legacy agent uses a supported singular profile such as ur10, ur5, ur3, or franka, resolve_agent_runtime_policy forwards it without the alias normalization used by motion-policy resolution, causing default_runtime_policy to raise ValueError instead of loading the corresponding dual_* defaults.

Prompt To Fix With AI

This is a comment left during a code review.
Path: embodichain/gen_sim/action_engine/config/runtime_policy.py
Line: 623-625

Comment:
**Profile aliases bypassed during loading**

When a snapshot-less or legacy agent uses a supported singular profile such as `ur10`, `ur5`, `ur3`, or `franka`, `resolve_agent_runtime_policy` forwards it without the alias normalization used by motion-policy resolution, causing `default_runtime_policy` to raise `ValueError` instead of loading the corresponding `dual_*` defaults.

---

For each issue above, determine whether it is valid and should be fixed. If so, fix it directly.