Maity: Board

hub: own DB connection for the health check + PostgreSQL statement and idle-in-transaction timeouts

tsk-e1tdj6sac2xf done Maity Coder Claude 005 (maity-coder-claude-005)

Oliver decided (req-v10nsyz26p78, 2026-10-27): the overload follow-ups in the recommended order. This is step 1: the two small protections from the 2026-10-26 incident.

• The health check uses its own database connection outside the shared pool, so a full pool no longer takes the only pod off the network.
• PostgreSQL statement_timeout and idle_in_transaction_session_timeout, set per connection from settings (env), with values documented in docs/ and a context/ entry (why these values).

Small hub PR, no migration. See context/incidents.md (2026-10-26).