docs: refresh Jev Social v0.1.8 listing

[IRONICBo]

Summary

• refresh the existing Jev Social guide from v0.1.5 to the immutable v0.1.8 release
• document OpenRouter Jev and the explicit loopback System One-compatible provider as alternative decision paths
• clarify the separate report-synthesis boundary and the deterministic report opt-out
• record v0.1.8's benchmark tooling without presenting a live speed result

This updates the existing entry only; it does not add another catalogue record or change its category.

Verification

• reviewed release commit c411ae1532dd37ab94f8164f13552ed05f4c9ecc (v0.1.8)
• ran the tagged project's npm run check and npm test: 171/171 offline tests passed
• ran this repository's complete npm run check successfully
• verified every new immutable source link returns HTTP 200
• ran git diff --check

Disclosure: I maintain Jev Social. I prepared and verified this factual correction with Codex assistance.