Add product template system for new contributions

[MrFixit96]

Summary

• Add reusable templates for contributing new products, plugins, and skills
• Follow patterns established by existing Terraform and Packer plugins
• Include discovery questions for agent-assisted automation

Structure

examples/
├── .claude-plugin/plugin.json
├── README.md                           # Comprehensive contributor guide
├── spec.md                             # GitHub Spec-Kit style template
├── questionnaire.md                    # Discovery questions for automation
├── commands/
│   └── new-product/
│       └── COMMAND.md                  # Interactive scaffolding command
└── new-product-template/
    └── {product}/
        ├── README.md.template
        └── {use-case}/
            ├── .claude-plugin/plugin.json.template
            └── skills/
                └── {skill-name}/SKILL.md.template

Changes

• Created examples/README.md with step-by-step instructions for adding products, plugins, and skills
• Created examples/spec.md GitHub Spec-Kit style specification template
• Created examples/questionnaire.md with discovery questions for agent automation
• Created examples/new-product-template/ with placeholder-based templates
• Created examples/commands/new-product/ for interactive scaffolding via /new-product
• Added CONTRIBUTING.md with contribution guidelines and workflow

Testing

• Templates validated against existing Terraform and Packer plugin structures
• All placeholder patterns ({product}, {use-case}, {skill-name}) documented

[hashicorp-cla-app]

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[MrFixit96]

Note on examples/ Directory

The examples/ directory contains a meta-plugin with a /new-product command for scaffolding new products interactively. This plugin is intentionally not registered in marketplace.json because:

1. It provides commands, not skills - The plugin has a commands/ directory rather than a skills/ directory
2. CI validation requires skills/ - The validation script expects all marketplace plugins to have a skills/ subdirectory
3. Local-only functionality - The scaffolding command is intended for contributors working locally, not for distribution via the marketplace

The plugin works correctly when the repository is cloned locally - users can run /new-product to interactively create a new product structure. It just does not need to be published to the marketplace since it is a development/contribution tool rather than an agent skill.