Added missing weight emails

docs/WEIGHT_REMINDER_TESTING.md

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+# Weight reminder tests
+
+From the repository root, run the unit tests and builds:
+
+```bash
+npm ci --prefix backend
+npm ci --prefix frontend
+npm test --prefix backend
+npm run build --prefix backend
+npm run build --prefix frontend
+```
+
+The integration test uses real Postgres 16, Redis 7, two worker processes, and
+Mailpit to capture SMTP messages locally. It requires Docker and free localhost
+ports 25432, 26379, 21025, and 28025. Port 21026 must remain unused for the SMTP
+failure check. Test addresses use `.test`; Mailpit does not relay mail externally.
+
+```bash
+docker compose -p flockpal-weight-test -f backend/test-integration/compose.weight-reminders.yml up -d --wait
+node backend/test-integration/weightReminders.mjs
+docker compose -p flockpal-weight-test -f backend/test-integration/compose.weight-reminders.yml down --volumes
+```
+
+Always run the last command when finished, including after a failed test. Start
+fresh containers for each run. Postgres data is disposable and held in tmpfs.
+The test overrides database, Redis, and SMTP environment variables to use only
+these local services. It does not use the application's configured SMTP account.
+
+Coverage includes repeatable schema initialization, overdue and recent weights,
+birds without weights, memorial exclusions, accepted care roles, concurrent
+claims, one scheduler across two workers, grouped emails, HTML escaping, flock
+isolation, 48-hour repeats, fresh weight resets, SMTP failures and recovery,
+worker shutdown, and disabling the scheduler. Repeat timing is tested by aging
+delivery timestamps rather than waiting two days.