Milestone 2: module/model docs (MD, Sphinx RST, PDF) and work log

74 source modules documented with extracted signatures, JSDoc params,
imports, and call graphs. 10 first-class models (PriceRule through
StatusResponse) have their own MD/RST/PDF. Sphinx HTML builds from
docs/sphinx. Per-module PDFs in docs/modules-pdf and docs/models-pdf.

Middleware gates 2–6 and 10 pass on MOCK_VERAE without NATS.

Learned: RST includes are relative to the RST file; keep one PDF per
module; Add Numbers remains the only push required tomorrow.

docs/modules/verae-zapier-middleware/nats/connection.md

@@ -0,0 +1,46 @@
+# `verae-zapier-middleware/nats/connection`
+
+**Package:** `verae-zapier-middleware`  
+**Source:** `packages/verae-zapier-middleware/src/nats/connection.js`  
+**Lines:** 112
+
+## What this module is
+
+Implementation module in `verae-zapier-middleware`. The tables below are extracted from the source (signatures + JSDoc).
+
+## Exports
+
+`connectNats`, `ensureStreams`, `closeNats`, `getJetStream`, `isNatsConnected`
+
+## Types / interfaces / classes
+
+_None extracted._
+
+## Functions
+
+| Name | Parameters | Param types (JSDoc) | Returns | Calls (same file / helpers) |
+|------|------------|---------------------|---------|-----------------------------|
+| `connectNats` | `url = config.natsUrl` | url: `string` | `Promise<{ nc: import('nats').NatsConnection, js: import('nats').JetStreamClient, jsm: import('nats').JetStreamManager ` — >} | see Call graph |
+| `ensureStreams` | `manager` | manager: `import('nats').JetStreamManager` | `Promise<void>` | see Call graph |
+| `closeNats` | `(none)` | — | `Promise<void>` | see Call graph |
+| `getJetStream` | `(none)` | — | `import('nats').JetStreamClient|null` | see Call graph |
+| `isNatsConnected` | `(none)` | — | `boolean` | see Call graph |
+
+## What it imports / requires
+
+- `../debug/logger.js`
+- `../config.js`
+- `./subjects.js`
+
+## Call graph (identifiers invoked)
+
+`createDebugger`, `import`, `connectNats`, `debug`, `disabled`, `info`, `connect`, `jetstream`, `jetstreamManager`, `ensureStreams`, `add`, `closeNats`, `drain`, `getJetStream`, `isNatsConnected`, `isClosed`
+
+Each identifier is a call site in this file. Follow the import list to see the defining module; open that module’s MD for parameter and return types.
+
+## Return values (how to read this)
+
+- HTTP route handlers return Express `res.json(...)` bodies (see route docs).
+- Zapier `perform` functions return a **single object** (creates) or an **array** (triggers/searches).
+- Pricing functions return integer **cents** on `Quote.totalCents`.
+