[codex] Add repository workflow documentation

[nickmoreton]

Summary

Goal

Document the repository workflow expectations for contributors and AI agents, add a shared pull request template, and align package metadata with the repository license.

Approach

Add contributor-facing workflow documentation in the repository root and docs/, update the in-repo agent guidance to match, add the GitHub pull request template used for future PRs, and set the project license metadata to MIT to match the new LICENSE file.

Affected Areas

• Repository workflow and contributor policy documentation
• Agent workflow guidance in AGENTS.md
• Pull request template under .github/
• Package metadata in package.json and pyproject.toml

Verification

• npm run format-check
• npm run test
• uv run python manage.py test

Documentation

• Added CONTRIBUTING.md
• Added docs/developer-onboarding.md
• Added .github/pull_request_template.md
• Updated README.md
• Updated AGENTS.md

Changelog

• Added an Unreleased entry in CHANGELOG.md covering the new repository workflow and agent publication policy.

Risks And Follow-Up

• This change documents and standardizes workflow expectations, but any GitHub repository settings that do not yet match the written policy still need to be kept in sync separately.

Screenshots

• N/A

[Copilot]

Pull request overview

This PR documents contributor and agent workflows for the repository, adds standardized PR documentation, and aligns license metadata with the repository’s MIT license.

Changes:

• Added contributor-facing workflow docs (CONTRIBUTING.md, docs/developer-onboarding.md) and updated README.md/AGENTS.md to reference them.
• Added a shared GitHub pull request template under .github/.
• Added an MIT LICENSE file and updated package metadata to reflect MIT licensing.

Reviewed changes

Copilot reviewed 9 out of 9 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
pyproject.toml	Adds license metadata for the Python project.
package.json	Updates npm package license field to MIT.
docs/developer-onboarding.md	New onboarding/workflow guide for developers.
README.md	Adds links and expectations for repo developer docs and PR structure.
LICENSE	Adds MIT license text.
CONTRIBUTING.md	New contributor workflow, checks, and agent publication gate policy.
CHANGELOG.md	Adds an Unreleased entry documenting the new workflow/policy.
AGENTS.md	Updates agent guidance to align with contributor workflow + PR template usage.
.github/pull_request_template.md	Adds a standardized PR template for future pull requests.

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[Copilot]

Pull request overview

Copilot reviewed 9 out of 9 changed files in this pull request and generated 1 comment.

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[Copilot]

Pull request overview

Copilot reviewed 9 out of 9 changed files in this pull request and generated 1 comment.

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