Draft ALL-905 Airbyte/Neon CDC investigation runbook (pre-unblock prep)

Forcing-function task from 2026-05-27 reflection to break the 12-day idle streak. ALL-905 has been blocked on Sergey for Airbyte / Neon postgres replication-slot inspection since 5/14. Draft a runbook NOW so when he unblocks, the work ships in hours not days. Content: (a) Airbyte connection inspection steps (which connection, which streams: IDENTITY_THIRDPARTY, SITE_WORKSPACESITE, DEVICES_SITEPROFILE — last extracted dates 2026-05-03, 2026-04-30, 2026-02-05 respectively); (b) Neon replication-slot health checks (queries to run, lag thresholds, restart-vs-recreate decision tree); (c) Solridge tenant cmaoa182l009o129ijkgvgzf8 — why is CDC tenant-specific?; (d) DEVICES_SITEPROFILE whole-table-stale hypothesis tree; (e) Verification queries against Snowflake post-fix. Deliverable: `~/agents/sergey-engineer/projects/all-905-runbook.md`, also linked into the ALL-905 Linear issue body. Pure prose + SQL work — no GH auth, no Sergey involvement required. Priority 3.