Steps to reproduce:
- Create a gift card program and a gift card with some balance
- Open a PoS session, add a product to a new order and enter the gift card code: a reward line is added and the total decreases
- Refresh the page, or leave the order and take it back from the Orders screen

Issue:
The reward line disappears and the total goes back to the full price, while the server still holds the pos.order.line with `is_reward_line`, `coupon_id` and `points_cost`. Nothing warns the cashier, so the customer can be charged for a service already paid with the card.

Cause:
`_code_activated_coupon_ids` is a local field of pos.order: it is neither stored in IndexedDB nor sent to the server, so it is empty once the order is rebuilt on the client. `_updateRewardLines` deletes every reward line and only re-applies the ones whose coupon is found in `_code_activated_coupon_ids` or in `uiState.couponPointChanges`. `updatePrograms` only rebuilds the latter for programs detectable from the order content, so a gift card, eWallet or coupon card activated by code is never recognised again and its reward is dropped by the next `updateRewards` call (TicketScreen.setOrder, barcode scan, partner change, line added...).

In 17.0 `codeActivatedCoupons` was exported and restored with the order; the field became local with the 18.0 models rewrite.

Fix:
Add `_restoreCodeActivatedCoupons` on pos.order and call it from `checkMissingCoupons`, which runs once per rebuilt order (`setup` flags it with `invalidCoupons`) before the programs and the reward lines are refreshed. It re-links every persisted coupon referenced by a reward line that is in neither structure. Nominative cards are excluded so that removing the partner still drops their reward.

opw-6568849

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Circular 99/2025/TT-BTC (effective FY2026) replaces Circular
200/2014/TT-BTC. The Profit & Loss statement (Mẫu B02-DN) gains a
new mandatory line, "Lãi/lỗ của hoạt động bán, thanh lý bất động sản
đầu tư" (mã số 21), computed from the new 5117/6327 sub-accounts
(see the paired l10n_vn commit). Financial income, financial
expenses and the interest memo line shift to mã số 22/23/24
accordingly, the "Net profit from operating activities" formula is
updated to include the new line, and all following line
numbers/labels are renumbered to match the printed form. The
interest memo line itself is renamed from "Chi phí lãi vay" to
"Chi phí đi vay" (Borrowing costs), per the gazette text.

Also, per revised guidance:
- Revenue and cost of goods sold now exclude the new investment
  property sub-accounts (5117/6327), so those amounts aren't
  double-counted between the main lines and the new gain/loss line.
- Other income is now computed from the "income_other" account type
  instead of a hardcoded account code, matching how the chart of
  accounts already classifies it.

Both the Balance Sheet and Profit and Loss VN reports also declare
an extra "Code" string column (for the printed-form mã số) alongside
"Balance". Core's growth-comparison heuristic only turns on the auto
growth-% column when there are exactly 2 total columns; with
Code+Balance that becomes 4 once a comparison period is added, so
the % never renders even though the underlying side-by-side
comparison values are fine. account.report exposes
filter_growth_comparison as a toggle independent from
filter_period_comparison for exactly this case (see Trial Balance
and the Deferred reports), so both reports set it to False: period
comparison stays available, only the auto growth-% column is
suppressed.

Task-6518304

Forward-Port-Of: odoo/enterprise#131085