feat(mcp): customer_number on create_customer + Beta tags on webshop surfaces (#1677)

* feat(mcp): accept customer_number on gnubok_create_customer

Parity with gnubok_update_customer: a customer number no longer needs a
create-then-update two-step with two approvals. The staged params carry
the trimmed number, commitCreateCustomer inserts it, and the payload-size
ceiling is bumped 59.7K to 59.75K with a documented entry (the property
has no description; name + maxLength are the whole contract).

Requested by a user on Discord 2026-08-16.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

* feat(ui): mark webshop integrations and orders tab as Beta

WooCommerce and Shopify rows on the import page get a quiet Beta chip
next to the title, and the webshop /orders sidebar item sets the
existing betaBadge flag. Chip recipe matches the nav beta badge so
Beta reads identically everywhere.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

* fix(mcp): enforce customer_number invariants and show it on the approval card

Consolidated resolution pass for PR #1677:
- skeptic (correctness): maxLength 32 was advertisement-only on the create
  path; now enforced with a runtime guard in gnubok_create_customer execute
  (clean errors for non-string and >32) and a 400 guard in
  commitCreateCustomer, matching the web/v1 routes and commitUpdateCustomer.
- skeptic (correctness): CustomerPreview never rendered the staged
  customer_number, leaving the approver blind to the new field; added a
  conditional Kundnr row.
- CodeRabbit: reset the event bus in create-customer.test.ts beforeEach.
- Tests cover both new guards at the tool and executor layers.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

---------

Co-authored-by: Claude Fable 5 <noreply@anthropic.com>

extensions/general/mcp-server/server.ts

@@ -4565,6 +4565,7 @@ export const tools: McpTool[] = [
           enum: ['individual', 'swedish_business', 'eu_business', 'non_eu_business'],
           description: 'Customer type',
         },
+        customer_number: { type: 'string', maxLength: 32 },
         email: { type: 'string', description: 'Email address' },
         org_number: { type: 'string', description: 'Swedish org number' },
         vat_number: { type: 'string', description: 'EU VAT number' },
@@ -4599,9 +4600,20 @@ export const tools: McpTool[] = [
         throw new Error('Invalid customer_type. Must be: individual, swedish_business, eu_business, non_eu_business')
       }
 
+      // Runtime guard (hosts don't always enforce inputSchema maxLength).
+      const customerNumberArg = args.customer_number
+      if (customerNumberArg != null && typeof customerNumberArg !== 'string') {
+        throw new Error('customer_number must be a string.')
+      }
+      const customerNumber = typeof customerNumberArg === 'string' ? customerNumberArg.trim() : ''
+      if (customerNumber.length > 32) {
+        throw new Error('customer_number must be at most 32 characters.')
+      }
+
       const params = {
         name: name.trim(),
         customer_type: customerType,
+        customer_number: customerNumber || null,
         email: (args.email as string) || null,
         org_number: (args.org_number as string) || null,
         vat_number: (args.vat_number as string) || null,