driftless 0.3.4

Added

• --generator fixture — key-free passing repair for bundled examples (support-classifier, rag-qa, tool-agent), so the published CLI can reproduce a successful migration without provider credentials.
• Contributor and operator docs — CONTRIBUTING.md, .env.example, eval-confidence guidance, and explicit 1.0 / GA criteria (CLI + Action, not a hosted bot).

Changed

• Hosted site adoption copy — landing and docs match configure --apply, inferred init-ci setup, and Action pin v0.3.4.
• Landing page story — hero has one primary CTA; scenario cards match their markup; outcomes show reproducible --generator none / --generator fixture paths; PR #4 is captioned as historical proof.
• Supported-surface limits — hosted GitHub App, catalog SaaS, and agent sandboxing are documented as out of scope rather than unfinished GA work.
• Live optimizer gate — scheduled runs on driftless-dev/driftless fail when no provider secrets are configured, instead of skipping green.
• Publish cold-install — after installing the wheel from PyPI, copy the bundled classifier example and run migrate --generator fixture.

Fixed

• Wheel metadata — cap hatchling below 1.30 so sdist/wheel emit Metadata-Version 2.4, which released twine and PyPI accept.