docs: document manual SFTP mode for this host (post-SP36)

- .env.example: add GAINWELL_SFTP_* mirror vars with bridge instructions
- .gitignore: exclude ingest/ + macOS AppleDouble residue
- CLAUDE.md: 'Production SFTP posture' section (env bridge, inbound drop
  zone, auth caveat, ingestion paths, daemon hot-reload caveat)
- docs/RUNBOOK.md: 'Manual SFTP mode' section (daily flow, backfill,
  parse-CLI caveat, manual→real switch procedure)

Recalibration after the auth-failed incident from 103.14.26.95 — local
SFTP uploads won't work until Gainwell whitelists this IP, so the
canonical flow is now manual file copy + cyclone pull-inbound.

CLAUDE.md

@@ -137,6 +137,34 @@ Config: `config/payers.yaml` is the on-disk source for providers / payers / clea
 
 Secrets live in the macOS Keychain (via `keyring` + `cyclone.secrets`): SQLCipher key (service `cyclone`, account `cyclone.db.key`), SFTP password, backup passphrase. No secrets on disk in plaintext.
 
+## Production SFTP posture (this box: manual mode)
+
+This host runs in **manual SFTP mode** against Gainwell's MOVEit Transfer MFT at `mft.gainwelltechnologies.com`. The seeded `dzinesco` clearhouse keeps `sftp_block.stub: true`; the operator moves files to/from Gainwell with their SFTP client and drops inbound files into `ingest/` for cyclone to ingest. Do NOT flip `stub` to `false` from this host — see "Auth caveat" below.
+
+### Env var convention
+
+The operator's shell exports the Gainwell creds as `GAINWELL_SFTP_USER`, `GAINWELL_SFTP_PASS`, `GAINWELL_SFTP_HOST`, `GAINWELL_REMOTE_DIR`. Cyclone's `secrets.get_secret()` looks up `CYCLONE_SFTP_PASSWORD` (or `CYCLONE_SFTP_PASSWORD_FILE`) per `secrets._ENV_NAME_FOR`. The two are NOT the same name — bridge them per-call or in your shell rc:
+
+```bash
+export CYCLONE_SFTP_PASSWORD="$GAINWELL_SFTP_PASS"
+```
+
+### Inbound drop zone
+
+`/home/tyler/dev/cyclone/ingest/` is the operator-maintained staging dir for inbound MFT files (999 acks, TA1, 835 remittances, 277CA claim acks). Files here are NOT auto-watched; processing happens via the procedure in `docs/RUNBOOK.md` § "Manual SFTP mode". At time of writing this dir holds ~1500 unprocessed 999 acks + 1 TA1 + 1 835 from early July 2026 — the local ingest flow clears them.
+
+### Auth caveat (do not retry)
+
+Paramiko reaches `MOVEit Transfer SFTP` cleanly (SSH kex completes, MOVEit offers password auth) but `AuthenticationException: Authentication failed` is returned despite the operator confirming the credentials are known-good from another host. Most likely cause: MOVEit Transfer's IP-based access control — this host's public IP `103.14.26.95` is not whitelisted. Repeated auth attempts risk account lockout. Do NOT keep guessing. Resolve by either: (a) whitelisting this IP with Gainwell's MFT admin, or (b) staying in manual mode and moving files via the operator's SFTP client.
+
+### Inbound ingestion paths
+
+The canonical way to write 999/TA1/277CA/835 rows into the DB is `Scheduler.process_inbound_files`, exposed as the CLI `cyclone pull-inbound --date YYYYMMDD` and the HTTP `POST /api/admin/scheduler/pull-inbound`. **There is no `parse-999` / `parse-ta1` / `parse-277ca` CLI command** (CLAUDE.md's "CLI" section above is aspirational on those three). The `parse-837` and `parse-835` CLIs exist but only emit JSON files to `--output-dir`; they do NOT write to the DB. For DB writes, use `pull-inbound` (which dedupes via `processed_inbound_files`).
+
+### Daemon hot-reload
+
+`python -m cyclone serve` runs as root (started by `tini`) and keeps the SFTP block in memory. Flipping `stub` directly in the DB (`store.update_clearhouse(...)`) does NOT auto-reload the daemon's view — either restart the daemon or use `PATCH /api/clearhouse` (which calls `scheduler.reconfigure_scheduler` to hot-reload).
+
 ## Frontend at a glance
 
 `src/` is React 18 + TypeScript + Vite. Routes register in `src/App.tsx` (11 pages, all under a `<Layout>` route wrapper). Pages are pure renderers — every page pairs with a `use<X>` data hook in `src/hooks/` and renders a `<PageHeader>` + a table/list/KPI grid. Drawers (`ClaimDrawer/`, `RemitDrawer/`, plus the new `ProviderDrawer/` and `AckDrawer/`) are mounted by the page and their open/close state is mirrored to the URL via `useDrawerUrlState` so deep-links round-trip. Drill-stack navigation is provided by `<DrillStackProvider>` in `src/components/drill/`.