ci: enforce health gate (remove continue-on-error; run ratchet:context normally)

[mojoatomic]

Summary

• Remove continue-on-error from health telemetry step
• Run ratchet:context normally (no || true) so gating can actually fail when enabled
• Keep job name ratchet-and-tests stable for branch protection

Behavior

• With health.enabled=false (default), step exits 0 and job passes
• With health.enabled=true and score below thresholds, step exits non-zero and job fails

Next (branch protection)

• Set ratchet-and-tests as a required check for main
• Optionally also require CI / Test on Node.js 20.x

Refs

• Health Gating Enforcement for Context-Aware Ratchet #203 Health Gating Enforcement
• feat(health): config-aware health gating (telemetry + optional gate) #208 health gating foundations
• feat: CI-safe init scripts + ratchet DX (examples, unlock hint) #212 ratchet DX improvements