Wires the IE + Schwab email parsers into an actual runnable sync. Walks
the IMAP mailbox, routes each message by sender domain:
- *@investengine.com → invest_engine.parse_invest_engine_email
- *@schwab.com → schwab.parse_schwab_email
then pushes the resulting Activities through the shared pipeline.
broker-sync imap-ingest — new CLI command taking IMAP_HOST/USER/PASSWORD/
DIRECTORY (mirrors the old wealthfolio-sync image's env shape so the
Terraform CronJob's existing env wiring works unchanged).
Verified: poetry run pytest -q → 109 passed + 1 skipped; mypy strict
clean (37 files); ruff + yapf clean.
