Add contribution guidelines and copyright assignment terms

[yoelrosenthal]

Changes

• Add the approved copyright assignment wording to CONTRIBUTING.md.
• Clarify that submitting a pull request does not obligate ByteMagic Inc. to accept, merge, release, or maintain it.
• Include brief submission guidelines and link the contribution terms from the README.

Verification

• Documentation links and the referenced README heading checked.
• git diff --check passed.
• Documentation only; no application code changed.

Note

Add CONTRIBUTING.md guidelines and copyright assignment terms

• Adds CONTRIBUTING.md with issue and pull-request expectations, copyright assignment to ByteMagic Inc., and contributor representations.
• Updates the contributing section in README.md to point to CONTRIBUTING.md alongside AGENTS.md.

^{Macroscope summarized 1fb97ff.}

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Summary by cubic

Adds contribution guidelines and copyright assignment terms so contributors know ByteMagic Inc. owns the copyright in submitted pull requests before they open one.

• Contributors assign copyright in their pull requests to ByteMagic Inc. and confirm they own or are authorized to assign those rights.
• Submitting a pull request does not obligate ByteMagic Inc. to accept, merge, release, or maintain it; AgentP stays under GPL-3.0-only.
• Adds brief submission guidelines and links CONTRIBUTING.md from the README's Contributing section.
• Documentation only; no application code changed.

^{Written for commit 8e65193. Summary will update on new commits.}

[cubic-dev-ai]

No issues found across 2 files

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