feat(scripts): helcim plan consolidation migration (dry-run default)

scripts/README.md

@@ -0,0 +1,51 @@
+# scripts/
+
+One-off admin and migration scripts. None of these run in CI.
+
+---
+
+## helcim-plan-consolidation.js
+
+Consolidates Helcim payment plans from the legacy per-tier model (multiple plans at $15/$30/$50) to two unified plans (Monthly Membership at $15, Annual Membership at $150), and backfills Mongo members.
+
+### Required env
+
+```
+HELCIM_API_TOKEN=<token>
+MONGODB_URI=<mongodb connection string>
+```
+
+Copy `.env.example` → `.env` if you haven't already.
+
+### Usage
+
+```bash
+# Dry-run (default) — no mutations, writes backup file
+node scripts/helcim-plan-consolidation.js
+
+# Execute all steps: delete subs, delete legacy plans, create new plans, update Mongo
+node scripts/helcim-plan-consolidation.js --confirm
+
+# Mongo cleanup only — skips all Helcim steps (use if Helcim steps already ran)
+node scripts/helcim-plan-consolidation.js --mongo-only
+```
+
+### What it does
+
+1. **Backup** — always written to `.migration-backup-<timestamp>.json`, even in dry-run. Contains all Helcim subscriptions, payment plans, and Mongo members with `helcimSubscriptionId`.
+2. **Delete subscriptions** — deletes all Helcim subscriptions (`--confirm` only).
+3. **Delete legacy plans** — deletes plan IDs `20162`, `21596`, `21597`, `21598`, plus any plan whose name matches the legacy pattern (e.g. "Ghost Guild - Member ($15)").
+4. **Create Monthly Membership** — $15/month. Idempotent: skipped if a plan named "Monthly Membership" already exists.
+5. **Create Annual Membership** — $150/year. Same idempotency. Uses `billingPeriod: "yearly"` (Helcim v2 convention); if Helcim returns 4xx, the script aborts and prints the full error so you can correct the field name.
+6. **Mongo cleanup** — `updateMany` with `runValidators: false` on all members with `helcimSubscriptionId`: sets `contributionTier: '0'` and `billingCadence: 'monthly'`, unsets `helcimSubscriptionId`. Does **not** change `status`.
+
+At the end, prints new plan IDs formatted for copy-paste into `.env`.
+
+### Recovery
+
+If something goes wrong mid-run, the backup JSON contains the pre-migration state. You can use the backup to:
+- Identify which subscriptions existed before deletion.
+- Identify which plan IDs to recreate manually in Helcim.
+- Identify which members had `helcimSubscriptionId` before it was unset.
+
+Backup files are gitignored (`.migration-backup-*.json`).