Default to America/Phoenix and email-alert once when the session expires

Phoenix doesn't observe DST, so schedule times stay meaningful
year-round without needing a seasonal adjustment.

notify.py reuses lunch-notifier's existing Gmail-SMTP-with-app-password
pattern rather than adding a new notification channel. The alert fires
exactly once per expiry (not on every failed scheduled run while it's
down) via a dedupe flag in notify_state.json, reset the moment a fresh
session is successfully imported.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01H6TgffxTvYhqxykAbVQg2v

.env.example

@@ -16,4 +16,16 @@ HOST_PORT=5057
 
 # ── Timezone ─────────────────────────────────────────────────────────
 # Controls what "6:00 AM" means for your schedules
-TZ=America/New_York
+TZ=America/Phoenix
+
+# ── Session-expiry email alert (optional) ───────────────────────────
+# Sent once when the saved MassPrice session expires/is missing — not
+# on every failed run, just the first one after it goes bad. Same
+# Gmail-app-password pattern as lunch-notifier: GMAIL_APP_PASSWORD is a
+# Gmail *app password* (Google Account → Security → App Passwords), not
+# your real Gmail password — required since Gmail blocks plain SMTP auth
+# with the account password. Leave blank to disable the alert entirely.
+GMAIL_USER=
+GMAIL_APP_PASSWORD=
+# Defaults to GMAIL_USER if left blank
+ALERT_EMAIL=