Tradier stack emitted account/positions/orders events hardcoded as
broker_name=alpaca_paper while the executor filters snapshots by
client.broker_name (tradier) — position cap and re-entry block read zero
positions, and the dashboard showed 'Alpaca Paper' over real Tradier values.
Mode label now defaults from BROKER/TRADIER_ENV (tradier_live) instead of
alpaca_paper.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>