feat(task-engine): add semantic task interpretation and grounding

[skywhite1024]

Description

Stack

• Stack: #539
• Layer: 3/7
• Base: ljd/gen-sim-refactor-02-seedgraph-contracts
• Depends on: feat(action-engine): add SeedGraph contracts and capabilities #533
• Followed by: feat(action-engine): add SeedGraph planning and bundle generation #535

Add the semantic task frontend shared by Task Engine and Action Engine. The layer provides typed instruction interpretation, candidate contracts, deterministic scene-reference grounding, role binding, scene hand-off validation, and robot-profile normalization without keyword fallbacks.

Refs #531

Type of change

• New feature (non-breaking change which adds functionality)

Validation

• Focused interpretation/grounding coverage - 19 passed
• Stack-tip GenSim regression - 706 passed, 9 warnings
• Black 26.3.1 - 855 Python files unchanged at the stack tip
• git diff --check - passed

Checklist

• Code passes Black 26.3.1.
• Tests cover the affected behavior.
• Stack-level architecture documentation is included by layer 7.
• No new third-party dependency is required.

[greptile-apps]

Greptile Summary

The PR adds scene-independent semantic task interpretation, candidate generation, scene grounding, TaskSpec assembly, scene handoff validation, and simulator configuration generation.

• Introduces strict Task Engine drafts, scene requests, success specifications, and candidate-set contracts.
• Adds LLM-backed instruction interpretation and scene-reference grounding for E1–E9 tasks.
• Adds Action Engine TaskSpec lowering and scene handoff validation.
• Adds robot-profile-driven simulator and agent configuration builders.

Confidence Score: 4/5

The PR is not safe to merge until the simulator templates required by build_fast_gym_config are added or its template references are corrected.

The semantic interpretation and grounding contracts appear internally consistent, but every invocation of the new gym-config builder reaches missing packaged templates and raises FileNotFoundError before producing a configuration.

Files Needing Attention: embodichain/gen_sim/action_engine/generation/config_builder.py and embodichain/gen_sim/action_engine/generation/templates/

Important Files Changed

Filename	Overview
embodichain/gen_sim/task_engine/interpretation.py	Adds strict LLM instruction interpretation, normalization, transport configuration, and intent validation.
embodichain/gen_sim/task_engine/agent.py	Adds concurrent candidate generation, canonicalization, deduplication, and vote aggregation.
embodichain/gen_sim/task_engine/contracts.py	Defines and validates JSON-safe task drafts, scene requests, success specifications, and candidate sets.
embodichain/gen_sim/action_engine/tasks/grounding.py	Adds fail-closed semantic scene-reference grounding with cardinality and eligibility checks.
embodichain/gen_sim/action_engine/tasks/interpretation.py	Bridges validated Task Engine intents into grounded Action Engine TaskSpecs.
embodichain/gen_sim/action_engine/tasks/assembly.py	Adds scene inventory modeling and E1–E9 TaskSpec and requirement assembly.
embodichain/gen_sim/action_engine/generation/config_builder.py	Adds simulator and agent manifest generation, but its required robot, sensor, and light templates are absent, making the new gym-config API fail immediately.

Flowchart

%%{init: {'theme': 'neutral'}}%%
flowchart LR
    I[Task instruction] --> TI[Task Engine interpretation]
    TI --> D[Validated semantic draft]
    D --> G[Scene-reference grounding]
    S[Scene inventory] --> G
    G --> TS[Grounded TaskSpec and scene requirements]
    TS --> H[Scene handoff validation]
    H --> C[Simulator and agent config generation]
    C --> R[Action Engine runtime]

Loading

Prompt To Fix All With AI

### Issue 1
embodichain/gen_sim/action_engine/generation/config_builder.py:225
**Required configuration templates are missing**

When `build_fast_gym_config()` runs, `_make_robot()` and the subsequent sensor and light loaders reference template files that are absent from this directory, causing generation to raise `FileNotFoundError` before returning a gym configuration. A/B mode also requires the absent `vlm_sensors.json`; please include the referenced templates or correct these references.

---

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

_{Reviews (1): Last reviewed commit: "feat(task-engine): add semantic task int..." | Re-trigger Greptile}

[greptile-apps]

Required configuration templates are missing

When build_fast_gym_config() runs, _make_robot() and the subsequent sensor and light loaders reference template files that are absent from this directory, causing generation to raise FileNotFoundError before returning a gym configuration. A/B mode also requires the absent vlm_sensors.json; please include the referenced templates or correct these references.

Prompt To Fix With AI

This is a comment left during a code review.
Path: embodichain/gen_sim/action_engine/generation/config_builder.py
Line: 225

Comment:
**Required configuration templates are missing**

When `build_fast_gym_config()` runs, `_make_robot()` and the subsequent sensor and light loaders reference template files that are absent from this directory, causing generation to raise `FileNotFoundError` before returning a gym configuration. A/B mode also requires the absent `vlm_sensors.json`; please include the referenced templates or correct these references.

---

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