chore: add Apache 2.0 + CC-BY-SA 4.0 dual licensing

[brawlaphant]

Summary

• Adds Apache License 2.0 (LICENSE) for all source code, scripts, schemas, and configuration files
• Adds CC-BY-SA 4.0 (LICENSE-CC-BY-SA) for all documentation, specifications, and design documents
• Adds LICENSE.md explaining the dual-license boundary with a clear directory/filetype mapping

Addresses Gregory's "No license set" open item.

License coverage

License	Applies to
Apache 2.0	agents/, agent-002-governance-analyst/, scripts/, schemas/, simulations/, reference implementations (*.js), schemas (*.json), configs
CC-BY-SA 4.0	docs/, phase-1/ through phase-5/, mechanism specs (SPEC.md), all *.md documentation

Test plan

• Verify GitHub recognizes the Apache 2.0 LICENSE file on the repo page
• Review LICENSE.md for accurate directory/file coverage
• Confirm contribution terms are clear

🤖 Generated with Claude Code

[gemini-code-assist]

Summary of Changes

Hello, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request introduces a comprehensive dual-licensing strategy for the repository, addressing a previously identified need for clear licensing terms. It systematically categorizes repository content into code-related assets, which are now covered by the Apache License 2.0, and documentation-related assets, which fall under the CC-BY-SA 4.0 license. This change provides explicit guidelines for intellectual property rights and contribution terms, enhancing legal clarity for all users and contributors.

Highlights

• Dual Licensing Model: Implemented a dual-license model for the repository to clearly distinguish between code and documentation assets.
• Apache License 2.0 for Code: Applied the Apache License 2.0 to all source code, scripts, schemas, and configuration files.
• CC-BY-SA 4.0 for Documentation: Applied the Creative Commons Attribution-ShareAlike 4.0 International license to all documentation, specifications, and design documents.
• License Explanation Document: Added a LICENSE.md file that explains the dual-license boundary, providing a clear mapping of directories and file types to their respective licenses.

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[gemini-code-assist]

Code Review

This pull request introduces a dual-licensing model for the repository, using Apache 2.0 for code and CC-BY-SA 4.0 for documentation. The LICENSE.md file outlines this model, specifying covered files and directories for each license. A review comment suggests clarifying the "When in doubt" rule in LICENSE.md to prevent mislicensing of non-Markdown documentation assets like diagrams, recommending a more explicit definition based on content purpose rather than just file extension.

[gemini-code-assist]

The "When in doubt" rule is a helpful simplification, but it could lead to incorrect licensing for documentation assets that are not in Markdown format. For example, diagrams (.svg, .png), design mockups, or other media included as part of the documentation would fall under "All other files" and be licensed as Apache 2.0. This contradicts the goal of licensing all documentation under CC-BY-SA 4.0.

To improve clarity and ensure all documentation assets are correctly licensed, I suggest expanding this rule to be more explicit about content types.

Here is a suggested replacement:

When in doubt, the file's purpose determines the license. As a general guideline:

- **Documentation and specifications** are licensed under **CC-BY-SA 4.0**. This includes but is not limited to Markdown files (`.md`), diagrams (`.svg`, `.png`, `.jpg`), and other media that are part of design documents.
- **Source code and configuration** are licensed under **Apache 2.0**. This covers the file types listed explicitly in the "Code" section above.