loop-engineer v0.5.0 — credibility enforcement + first screen

The two pre-launch milestones of the v1.0 roadmap, landed together.

Enforce the wedge — false-completion defense is now enforced by validators, not asserted by docs:

• A Succeeded terminal no longer validates with false_completion: true or an empty/false criteria_met; the inspector grades false-completion defense on invocation evidence, never a self-asserted flag (#8).
• The held-out gate returns NotReady on an empty visible set; the anti-cheat scanner detects edits that neuter its own gate-decision functions and reports gate tampering with a distinct exit code (#8).
• examples/coverage-repair runs end-to-end through the real held-out gate — its false_completion: false is backed by a committed gate verdict, not a hand-set flag (#9).
• The repo's own live contract passes its own gate: python3 -m loop doctor .loop → ok (#8).

First screen — a stranger gets it in 10 seconds, scores a loop in 30:

• README rebuilt: tagline, concrete failure modes, zero-install first command, stack diagram, comparison table (#7, #12).
• Weak→strong demo filmed live on the real tools: docs/demo.gif — a self-asserted DIY loop scores 0/weak, the gate-backed example 90/strong (#13).
• New loop scaffold command + JSON Schemas for the contract artifacts; promised templates shipped (#8, #11).
• CLI polish: --help/--version, distinct errors, explicit exit codes (#10).

Plus: the v1.0 master roadmap and four strategic design specs are now committed under docs/superpowers/ (#15).

Version jumps 0.3.4 → 0.5.0 to match the roadmap's milestone numbering; there is no 0.4.x tag.

Full details in CHANGELOG.md.