feat: accounting module — schema, migration, Zod schemas, AR balance service

Phase 1 foundation:
- Migration 0047: all accounting tables (invoice, payment_application,
  account_balance, account_code, journal_entry, billing_run), chart of
  accounts seed, nextBillingDate on enrollment, accounting module config
- Drizzle schema file with all table definitions and type exports
- Zod validation schemas (invoice, payment, billing, reports)
- AccountBalanceService: materialized AR balance per account

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

packages/shared/src/schemas/accounting.schema.ts

@@ -0,0 +1,83 @@
+import { z } from 'zod'
+
+// Enums
+export const AccountType = z.enum(['asset', 'liability', 'revenue', 'contra_revenue', 'cogs', 'expense'])
+export type AccountType = z.infer<typeof AccountType>
+
+export const InvoiceStatus = z.enum(['draft', 'sent', 'paid', 'partial', 'overdue', 'void', 'written_off'])
+export type InvoiceStatus = z.infer<typeof InvoiceStatus>
+
+export const JournalLineType = z.enum(['debit', 'credit'])
+export type JournalLineType = z.infer<typeof JournalLineType>
+
+export const BillingRunStatus = z.enum(['pending', 'running', 'completed', 'failed'])
+export type BillingRunStatus = z.infer<typeof BillingRunStatus>
+
+// Invoice
+export const InvoiceLineItemInput = z.object({
+  description: z.string().min(1).max(255),
+  qty: z.coerce.number().int().min(1).default(1),
+  unitPrice: z.coerce.number().min(0),
+  discountAmount: z.coerce.number().min(0).default(0),
+  taxRate: z.coerce.number().min(0).default(0),
+  accountCodeId: z.string().uuid().optional(),
+})
+export type InvoiceLineItemInput = z.infer<typeof InvoiceLineItemInput>
+
+export const InvoiceCreateSchema = z.object({
+  accountId: z.string().uuid(),
+  locationId: z.string().uuid().optional(),
+  issueDate: z.string().regex(/^\d{4}-\d{2}-\d{2}$/),
+  dueDate: z.string().regex(/^\d{4}-\d{2}-\d{2}$/),
+  notes: z.string().optional(),
+  lineItems: z.array(InvoiceLineItemInput).min(1),
+})
+export type InvoiceCreateInput = z.infer<typeof InvoiceCreateSchema>
+
+export const PaymentApplicationSchema = z.object({
+  transactionId: z.string().uuid().optional(),
+  amount: z.coerce.number().min(0.01),
+  notes: z.string().optional(),
+})
+export type PaymentApplicationInput = z.infer<typeof PaymentApplicationSchema>
+
+export const InvoiceVoidSchema = z.object({
+  reason: z.string().min(1),
+})
+export type InvoiceVoidInput = z.infer<typeof InvoiceVoidSchema>
+
+export const InvoiceWriteOffSchema = z.object({
+  reason: z.string().min(1),
+})
+export type InvoiceWriteOffInput = z.infer<typeof InvoiceWriteOffSchema>
+
+// Journal Entry
+export const JournalEntryVoidSchema = z.object({
+  reason: z.string().min(1),
+})
+export type JournalEntryVoidInput = z.infer<typeof JournalEntryVoidSchema>
+
+// Billing
+export const BillingRunSchema = z.object({
+  runDate: z.string().regex(/^\d{4}-\d{2}-\d{2}$/).optional(),
+})
+export type BillingRunInput = z.infer<typeof BillingRunSchema>
+
+export const BillEnrollmentSchema = z.object({
+  periodStart: z.string().regex(/^\d{4}-\d{2}-\d{2}$/),
+  periodEnd: z.string().regex(/^\d{4}-\d{2}-\d{2}$/),
+})
+export type BillEnrollmentInput = z.infer<typeof BillEnrollmentSchema>
+
+// Report filters
+export const DateRangeFilterSchema = z.object({
+  dateFrom: z.string().regex(/^\d{4}-\d{2}-\d{2}$/).optional(),
+  dateTo: z.string().regex(/^\d{4}-\d{2}-\d{2}$/).optional(),
+})
+export type DateRangeFilter = z.infer<typeof DateRangeFilterSchema>
+
+export const StatementFilterSchema = z.object({
+  from: z.string().regex(/^\d{4}-\d{2}-\d{2}$/),
+  to: z.string().regex(/^\d{4}-\d{2}-\d{2}$/),
+})
+export type StatementFilter = z.infer<typeof StatementFilterSchema>

packages/shared/src/schemas/index.ts

@@ -200,3 +200,31 @@ export type {
 
 export { LogLevel, AppConfigUpdateSchema } from './config.schema.js'
 export type { AppConfigUpdateInput } from './config.schema.js'
+
+export {
+  AccountType,
+  InvoiceStatus,
+  JournalLineType,
+  BillingRunStatus,
+  InvoiceLineItemInput,
+  InvoiceCreateSchema,
+  PaymentApplicationSchema,
+  InvoiceVoidSchema,
+  InvoiceWriteOffSchema,
+  JournalEntryVoidSchema,
+  BillingRunSchema,
+  BillEnrollmentSchema,
+  DateRangeFilterSchema,
+  StatementFilterSchema,
+} from './accounting.schema.js'
+export type {
+  InvoiceCreateInput,
+  PaymentApplicationInput,
+  InvoiceVoidInput,
+  InvoiceWriteOffInput,
+  JournalEntryVoidInput,
+  BillingRunInput,
+  BillEnrollmentInput,
+  DateRangeFilter,
+  StatementFilter,
+} from './accounting.schema.js'