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/zappier/jobs/report-usage.md

@@ -0,0 +1,63 @@
+# `zappier/jobs/report-usage`
+
+**Package:** `zappier`  
+**Source:** `packages/zappier/src/jobs/report-usage.ts`  
+**Lines:** 130
+
+## What this module is
+
+Implementation module in `zappier`. The tables below are extracted from the source (signatures + JSDoc).
+
+## Exports
+
+`ReportUsageDeps`, `REPORT_USAGE_LOCK`, `firstOfMonthUtc`, `reportMonthlyUsage`
+
+## Types / interfaces / classes
+
+| Kind | Name |
+|------|------|
+| interface | `ReportUsageDeps` |
+
+## Functions
+
+| Name | Parameters | Param types (JSDoc) | Returns | Calls (same file / helpers) |
+|------|------------|---------------------|---------|-----------------------------|
+| `firstOfMonthUtc` | `now: Date` | — | `unknown` | see Call graph |
+| `reportMonthlyUsage` | `deps: ReportUsageDeps` | — | `unknown` | see Call graph |
+| `main` | `(none)` | — | `unknown` | see Call graph |
+
+## Methods (class / object)
+
+| Name | Parameters |
+|------|------------|
+| `loadEnv` | `{ path: path.join(PROJECT_ROOT, '.env'` |
+| `main` | `(none)` |
+
+## What it imports / requires
+
+- `better-sqlite3`
+- `path`
+- `stripe`
+- `../app`
+- `../auth`
+- `../billing/stripe`
+- `../db/billing-repo`
+- `../db/customer-repo`
+- `../db/pricing-store`
+- `../db/usage-repo`
+- `../paths`
+- `../pricing`
+- `../usage`
+
+## Call graph (identifiers invoked)
+
+`firstOfMonthUtc`, `setUTCDate`, `setUTCHours`, `reportMonthlyUsage`, `tryAcquireLock`, `log`, `toISOString`, `slice`, `list`, `find`, `warn`, `listFor`, `computeBillableCents`, `getReportedCents`, `computeDelta`, `createMeterEvent`, `upsertReportedCents`, `releaseLock`, `main`, `import`, `loadEnv`, `join`, `async`, `create`, `getTiers`, `error`, `exit`
+
+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`.
+