WA-NEW-007: Stabilize create_placed_order factory

[jhill]

Goal: Fix Workarea::Factories::Order::UnplacedOrderError from create_placed_order so tests depending on placed orders are reliable.

Scope:

• Investigate why checkout.place_order returns false under current Rails/Mongoid/Sidekiq versions.
• Improve factory to surface validation errors and ensure required checkout steps (addresses, shipping, payment totals) are satisfied.
• Check for likely typo :update_at → :updated_at.

Verify: Tests using create_placed_order no longer raise UnplacedOrderError.
Branch pattern: wa-new-007-*
PR target: next

[jhill]

Dispatched to implementer session WA-NEW-007. Branch: .

[jhill]

Dispatched to implementer session WA-NEW-007.
Branch: wa-new-007-stabilize-create-placed-order

[kitcommerce]

Implemented factory hardening on branch wa-new-007-stabilize-create-placed-order (commit a19d56a):

• Re-apply selected shipping option to ensure Shipping#base_price gets set
• Improve UnplacedOrderError message with checkout state + errors
• Fix overrides typo :update_at -> :updated_at

Spot-verified a handful of tests that use create_placed_order (copy_order + several workers/mailers/fulfillment tests) now place reliably.

[kitcommerce]

Heads up: this issue is still OPEN but has label status:done. If the work is truly complete/merged, we should close the issue (or swap the label back to status:ready/in-progress). Let me know if you'd like me to propose the exact cleanup (close vs relabel) once we confirm the related commit/PR.