contrib(common-utilities): add docx-conversion and parallel-combinator utilities

[rogelsm]

Library Contribution

Type: process (reusable task definitions)
Name: common-utilities
Specialization: common-utilities
Location: plugins/babysitter/skills/babysit/process/specializations/common-utilities/

Description

Two reusable library modules extracted from a retrospective analysis of essay-critique, extract-oral-prep, and essay-grading processes:

1. docx-conversion.js

A shared HTML-to-DOCX conversion task using pandoc with graceful fallback. This identical pattern was duplicated across multiple process files and has been extracted into a reusable module.

• Uses defineTask with kind: 'shell'
• Gracefully falls back when pandoc is not installed
• Returns structured JSON with success status and converter info

2. parallel-combinator.js

Utility functions for parallel task execution with fan-out/fan-in patterns:

• fanOutFanIn(ctx, sharedArgs, taskSpecs) - Run multiple tasks in parallel with shared input
• pipeline(ctx, initialInput, phases) - Sequential phases with optional parallel steps, accumulating results

3. index.js

Re-exports all modules for clean importing.

4. README.md

Documentation with usage examples for both modules.

Files Added

• plugins/babysitter/skills/babysit/process/specializations/common-utilities/docx-conversion.js
• plugins/babysitter/skills/babysit/process/specializations/common-utilities/parallel-combinator.js
• plugins/babysitter/skills/babysit/process/specializations/common-utilities/index.js
• plugins/babysitter/skills/babysit/process/specializations/common-utilities/README.md

Quality Checks

• ✅ Structure check: PASS
• ✅ Lint: PASS
• ✅ Library pattern validation: PASS

Origin

Identified during retrospective analysis of babysitter orchestration runs. The docx-conversion task was duplicated identically in 2 process files. The parallel combinator pattern was used manually via Promise.all but benefits from standardization.