Adds Discord as a second connector adapter on the shared core: signed interactions for answer buttons, one gateway worker (same image, single leader by database lock, commits on the lock's connection, checkpoints for resume), thread posts through the shared post queue, owner-only control, and teammate context only from linked accounts. Inert until the Discord settings are configured. A narrow gitleaks allowlist entry covers connector Discord env var names in config errors.
Moves the push gateway's database layer into a shared cloud/packages/cloud-database package (service name and schema passed in). Push's behaviour, log names, SQLite file and tests are unchanged.
Jinwoo Hong