Add awesome-ai-companion to Reference Repo

[DasterProkio]

Adds awesome-ai-companion under Reference Repo.

What it is: a curated index of long-term AI companion systems — chat clients, memory and identity layers, proactive behavior engines, embodiment, shared activities, and continuity tooling. 160 entries, each tagged with language, platform, and a readiness status (ready / adapt / verify / infra). Full Chinese translation kept in sync.

Why it fits the quality bar:

• Repository is CC0 licensed and public since 2026-07-03; every linked project was checked against its own source or docs, not marketing copy.
• Entries carry factual caveats where relevant (e.g. unmaintained upstreams, non-commercial licenses, missing client source), so readers can judge before investing time.
• Complements the existing agent-focused reference lists: this one covers the persistent-relationship side of agents — memory continuity, proactive contact timing, and embodiment — rather than task-solving or coding harnesses.
• Passes npx awesome-lint; link checking covers all 148 linked GitHub repositories.

Web index: https://lutopia.app/companion/