feat(maestro-case): delegate HITL action task authoring

[song-zhao-25]

What

Refactors the uipath-maestro-case action path so Case owns orchestration intent and delegates HITL resource authoring to uipath-human-in-the-loop.

Every approved, non-placeholder action task is handed to the HITL skill during Phase 2. Case no longer carries a private QuickForm/App JSON recipe or constructs action sidecars, context, resource bindings, recipients, or runtime I/O itself.

Ownership boundary

Case owns	uipath-human-in-the-loop owns
target stage/lane and task ordering	QuickForm/App-specific schema representation
required/run-once flags and task-entry conditions	action JSON and HITL-owned artifacts
approved business input/output/outcome rows	action-internal bindings and runtime I/O
Case variables and cross-task producer/xref contract	recipient/App encoding and HITL validation
Action App registry selection and persisted I/O contract	optional App contract re-verification
downstream Case bindings and final Case validation	returning the written task/artifact identifiers

Delegations run sequentially against the shared caseplan.json. Case re-reads and verifies target placement, IDs, non-empty action data, and returned artifacts after each delegation. If the skill is unavailable or the result cannot be verified, Case writes the standard structural action placeholder with data: {} and records a build issue. It never improvises HITL JSON.

This follows the repository isolation rule: there is no structural cross-skill dependency and Case never reads or copies sibling skill files. The dependency is a runtime handoff with a graceful placeholder fallback.

Planning and I/O handoff

The approved SDD remains the business contract. tasks.md preserves:

• the requested QuickForm or deployed Action App path;
• title, priority, typed recipient, labels, and app actionType;
• exact Input Schema, Output Schema, and outcomes;
• Case-normalized outputs: producer rows for lineage and cross-task references;
• selected Action App registry metadata plus its persisted tasks describe I/O contract.

That information is passed to the HITL delegate as a self-contained brief. Case does not translate it into field directions, native HITL types, sidecar properties, context entries, or runtime arrays.

Relationship to #2056

This PR has a strong behavioral/runtime dependency on #2056, but no file-level dependency.

• feat(maestro-case): delegate HITL action task authoring #2116 supplies Case orchestration and the complete handoff contract.
• feat(hitl-skill): add Case Management surface — hitl-casetask-action.md + SKILL.md routing #2056 must consume that contract and correctly author the Case QuickForm/App artifacts, including complete runtime input/output mappings.
• Without a compatible feat(hitl-skill): add Case Management surface — hitl-casetask-action.md + SKILL.md routing #2056 implementation, delegation degrades to a placeholder and the end-to-end QuickForm regression does not pass.

#2056 is intentionally out of scope for this PR and will be fixed by its owning team. Keep #2116 draft/held until the compatible #2056 fix is available in the integration base.

Regression coverage

The existing quickform_runtime_io integration task now verifies both halves of the contract:

• skill_triggered requires uipath-human-in-the-loop to be invoked by the Case build;
• the deterministic checker verifies QuickForm sidecar/task I/O parity;
• solution packing must retain HitlTaskArguments input and output mappings in BPMN;
• QuickForm still has no deployed-app binding or registry audit entry.

Verification

Passed locally:

• git diff --check
• skill-creator quick_validate.py skills/uipath-maestro-case
• npm run version:check
• python3 scripts/check-skill-status.py --check-readme
• coder-eval plan for quickform_runtime_io.yaml
• task CLI-verb lint
• checker script parse/help smoke

A full local coder-eval execution still requires an authenticated Claude CLI and the compatible #2056 implementation. The existing maestro-case checker unit tests CI failure is an unrelated pytest collection collision between two pre-existing test_checkers.py modules; this PR does not modify either module.