Align store calls with selected-company scoping and add entity numbers.

Drop companyId from company-scoped store wrappers and routes, add GET /entity/next-number plus optional number on entity create/update, and document dashdbschema API.md lookup in sibling-repos.

src/api/openapi.js

@@ -148,7 +148,7 @@
  *                 `PUT /customergroup/order`.
  *     Entity:
  *       type: object
- *       required: [id, customergroupId, firstName, name, createdAt, updatedAt]
+ *       required: [id, customergroupId, firstName, name, number, createdAt, updatedAt]
  *       properties:
  *         id:
  *           type: integer
@@ -159,6 +159,10 @@
  *           nullable: true
  *         name:
  *           type: string
+ *         number:
+ *           type: string
+ *           nullable: true
+ *           description: Customer number (null for suppliers)
  *         createdAt:
  *           type: string
  *           format: date-time