Scaffold a new skill for hms-commander

Scaffold a new skill for hms-commander following the existing skill structure.

Skill Structure

.claude/skills/{skill_name}/
├── SKILL.md          # Main skill document (required)
├── examples/         # Working code examples (optional)
│   └── *.md
└── reference/        # Detailed API docs (optional)
    └── *.md

Step 1: Create Skill Directory

mkdir .claude/skills/{skill_name}

Step 2: Create SKILL.md

Use this template (see hms_execute_runs/SKILL.md for a full example):

---
name: {skill_name}
description: |
  One paragraph description of what this skill does.
  Trigger keywords: key, terms, that, invoke, this, skill.
---

# {Skill Title}

## Quick Start

Minimal working example to accomplish the core task.

## Primary Sources

**Code (Authoritative API)**:
- `hms_commander/{MainClass}.py` — Complete docstrings

**Examples (Working Demonstrations)**:
- `examples/{NN_notebook}.ipynb` — Cells X-Y

**Rules (Patterns & Decisions)**:
- `.claude/rules/hec-hms/{relevant-rule}.md`

## When to Use This Skill

**Trigger Scenarios**:
- User says "..."
- User mentions "..."

## Core Capabilities

### Capability 1
Pattern description.

## Common Workflows

### Workflow 1: Title
```python
# Code example

Troubleshooting

Common issues and solutions.

Integration Points

Before this skill: What to do first After this skill: What to do next

Related Skills

• other_skill — Description

## Step 3: Add Examples (Optional)

Create `examples/` with markdown files showing real usage patterns.

## Step 4: Update INDEX.md

Add the new skill to `.claude/INDEX.md` "Active Skills" table:

```markdown
| **{skill_name}/** | Purpose description | trigger, keywords, here |

Skill Naming Conventions

• Directory name: snake_case (e.g., hms_execute_runs)
• Main file: SKILL.md (always uppercase)
• Examples: kebab-case.md (e.g., basic-run.md)

Reference

• Example full skill: .claude/skills/hms_execute_runs/SKILL.md
• Simpler skill: .claude/skills/hms_clone_components/SKILL.md
• Index: .claude/INDEX.md "Skills" section