chore: add community health files and release title format

[eschaar]

Summary

• add community health files: Code of Conduct, Contributing, Security Policy
• add issue templates and pull request template
• add CODEOWNERS
• update release workflow to use title format: Release vX.Y.Z (YYYY-MM-DD)

Validation

• pre-commit hooks passed for committed files

[Copilot]

Pull request overview

Adds standard GitHub community health files and repository templates, and updates the release workflow’s GitHub Release title to include a Release vX.Y.Z (YYYY-MM-DD) format.

Changes:

• Added community health documentation: Code of Conduct, Contributing guide, and Security policy.
• Added GitHub issue templates, PR template, and CODEOWNERS for contribution triage and ownership.
• Updated release workflow to compute a UTC release date and use it in the GitHub Release title.

Reviewed changes

Copilot reviewed 9 out of 9 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
SECURITY.md	Defines supported versions and a private vulnerability reporting process via Security Advisories.
CONTRIBUTING.md	Documents prerequisites, setup steps, workflow expectations, and commit message guidance.
CODE_OF_CONDUCT.md	Establishes expected/unacceptable behavior and reporting/enforcement guidance.
.github/workflows/release.yml	Adds a step to compute a UTC date and updates the GitHub Release name format.
.github/pull_request_template.md	Adds a standardized PR template including validation and release impact checklist.
.github/ISSUE_TEMPLATE/feature_request.yml	Adds a structured feature request issue form.
.github/ISSUE_TEMPLATE/bug_report.yml	Adds a structured bug report issue form.
.github/ISSUE_TEMPLATE/config.yml	Disables blank issues and routes security reports to Security Advisories.
.github/CODEOWNERS	Establishes default repository ownership for review routing.