Initial scaffold: Flask webui + APScheduler + Playwright automation for MassPrice rule scheduling

Drives massprice.tcgplayer.com's Run Rule action per-rule on a
user-configured schedule (multiple times/day, day-of-week toggles),
replacing MassPrice's native scheduler (capped at 15 schedules
account-wide, one run/day, with observed clock drift). Deployed via
Forgejo push-to-deploy on Unraid, matching arr-summary/card-grader.

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

.env.example

@@ -0,0 +1,26 @@
+# ══════════════════════════════════════════════════════════════════
+#  MassPrice Scheduler — Environment Variables
+#  Copy this file to .env and fill in your values.
+# ══════════════════════════════════════════════════════════════════
+
+# ── Login (this tool's own login page, not your MassPrice account) ─
+LOGIN_PASSWORD=changeme
+
+# Secret key for Flask session signing — generate a random string:
+#   python3 -c "import secrets; print(secrets.token_hex(32))"
+SECRET_KEY=change_this_to_a_random_secret_key
+
+# ── MassPrice (TCGplayer) login ─────────────────────────────────────
+# Used by Playwright to log in automatically the first time, and again
+# any time the saved session expires. Stored here only — gitignored,
+# never committed, never logged.
+MASSPRICE_USERNAME=your_tcgplayer_email@example.com
+MASSPRICE_PASSWORD=your_tcgplayer_password
+
+# ── Host port (what port Unraid exposes) ────────────────────────────
+# Default is 5056 (arr-summary already uses 5055) — change if in use
+HOST_PORT=5056
+
+# ── Timezone ─────────────────────────────────────────────────────────
+# Controls what "6:00 AM" means for your schedules
+TZ=America/New_York