docs: competitive analysis of yc-software/qm (2026-08)

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What

Adds docs/competitive/qm-2026-08.md — the full competitive analysis of yc-software/qm, the multiplayer agent harness YC open-sourced on 2026-07-29.

Contents

• Quality assessment (production-maturity signals, weaknesses)
• Architecture deep dive: scope/audience-floor model, harness abstraction, durable per-scope sandbox, security postures + provenance screening, memory, background work, operations
• Surfaces: plugin coupling, Slack depth, skills lifecycle, credential keychain/broker, internal-app publish, deployment-directory contract
• Comparison with omadia: shared ground, gaps on both sides, and an honest-mirror section on our own claim gaps
• The eight adoption candidates, linked to issues Scope model with audience-floor permission intersection for shared rooms #575–Deployment-directory contract with agent-run deployment #582 (label from-qm)

Notes for reviewers

• This is a public repo — the doc includes candid self-assessment (Slack claim ahead of code, "signed plugins" wording, in-process plugin isolation). Flagging deliberately; trim if we'd rather keep any of it internal.
• Doc-only change, no code touched.

🤖 Generated with Claude Code

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