Release v0.3.0

Added

• Add runtime validation for benchmark metric names, implementation names, case
  names, work-unit names, empty matrices, non-callable implementations, and
  invalid case values.
• Add runnable factorial examples documentation and tests that verify example
  benchmark matrices remain collectable.
• Add docs section landing pages, a Project docs section, improved MkDocs
  navigation styling, and a prominent README link to the published docs site.
• Add pre-push make check automation and expanded workflow linting through
  pre-commit.

Changed

• Reorganize project documentation under docs/project/ and align README,
  package metadata, docs navigation, and runbook indexes with the published
  documentation site.
• Expand Ruff, basedpyright, pytest, coverage, spelling, and ignored-directory
  configuration to cover examples, scripts, docs helpers, and repository
  automation more consistently.
• Improve Docker, .dockerignore, and devcontainer setup for reproducible uv,
  Node, Docker, and Codex-compatible development workflows.
• Harden release helper scripts and tests around release-note output, existing
  release PR reuse, duplicate local tag detection, and warning-only preflight
  checks.

Removed

• Remove local-only devcontainer mounts and run arguments from the shared
  devcontainer configuration.

Fixed

• Prefer pytest-benchmark name with fullname as a fallback when parsing
  benchmark JSON rows.
• Handle repositories without GitHub Actions workflow files when running
  workflow linting.