docs: add CODEOWNERS, CONTRIBUTING, and AGENTS development guides

[jdhoffa]

This PR adds repository governance and contributor/agent guidance files:

• .github/CODEOWNERS: Sets @jdhoffa as code owner for the full repository.
• CONTRIBUTING.md: Adds contribution process guidance (issues/discussions, PR expectations, testing/docs requirements, code ownership review expectations, and issue-prefixed
  branch naming convention).
• AGENTS.md: Adds repository-specific instructions for coding agents (commands, directory structure, workflow expectations, issue/PR behavior).

[github-actions]

Docs preview was removed because this PR is closed.

[Copilot]

Pull request overview

This PR establishes repository governance and development guidelines by adding three foundational documentation files. The changes provide clear expectations for contributors and coding agents, define code ownership, and establish process conventions for issues, PRs, and commits.

Changes:

• Added CODEOWNERS file designating @jdhoffa as owner for all repository files
• Added CONTRIBUTING.md with contribution guidelines covering issue/PR workflow, testing, documentation requirements, and commit conventions
• Added AGENTS.md with agent-specific development instructions including commands, directory structure, and workflow expectations

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 2 comments.

File	Description
.github/CODEOWNERS	Sets @jdhoffa as code owner requiring review approval for all changes
CONTRIBUTING.md	Defines contribution process, coding standards, branch/commit conventions, and documentation requirements
AGENTS.md	Provides coding agent guidance on commands, repository structure, and development workflow

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[Copilot]

The branch naming example uses mixed separators: a hyphen between the issue number and descriptor (23-) but underscores within the descriptor (http_telemetry_range). For consistency, consider using hyphens throughout (e.g., 23-http-telemetry-range) or explicitly state that underscores should be used within descriptors while hyphens separate the issue number.

Suggested change

	- Branch names: prefix with the GitHub issue number when appropriate, then a short descriptor (e.g., `23-http_telemetry_range`).
	- Branch names: prefix with the GitHub issue number when appropriate, then a short descriptor using hyphens as separators (e.g., `23-http-telemetry-range`).

[Copilot]

The reference to docs/ directory is incorrect. The repository does not have a docs/ directory. The documentation is generated from Rustdoc (as shown in .github/workflows/docs.yml) and deployed to GitHub Pages, not stored in a docs directory. Consider removing this reference or clarifying that documentation refers to Rustdoc comments in source files.

Suggested change

	- Project documentation: `README.md`, `docs/`, `CONTRIBUTING.md`
	- Project documentation: `README.md`, Rustdoc comments in `src/`, `CONTRIBUTING.md` (Rustdoc-generated API docs are published via GitHub Pages)