feat(procurement): PR #12 Track A suppliers + PO + GRN baseline

[rmak78]

Summary

Implements PR #12 – Track A (Procurement baseline) on a branch from main.

What’s included

• Added D1 migration: data-model/migrations/0007_procurement_suppliers_po_grn.sql

  • suppliers
  • purchase_orders
  • purchase_order_lines
  • goods_receipts
  • goods_receipt_lines
  • Supporting indexes for lookup/status/date queries

• Added v1 API endpoints in src/index.ts:

  • GET/POST /v1/suppliers
  • GET/POST /v1/purchase-orders (supports optional line inserts in payload)
  • GET/POST /v1/goods-receipts (supports optional lines, inventory increment on accepted qty, PO-line received qty update, PO status progression)

• Updated API discovery and auth/write route handling:

  • Added procurement routes to /v1 route list
  • Added procurement module in /v1/modules
  • Added write-protected paths for POST endpoints

• Updated README.md route listing with procurement endpoints.

Validation

• Ran deployment compile check successfully:
  • npx wrangler deploy --dry-run

Notes

• Baseline scope only for supplier/PO/GRN foundations.
• Additive migration only (no destructive schema changes).

[rmak78]

Superseded by canonical merged PRs (#24 for procurement, #20/merged path for returns). Closing to keep backlog clean.