Release 2026w26

Grouped invoice-ledger entries, quarterly billing, Positive Pay exports, enhanced entity and matter forms, and targeted reliability fixes.

• +AddedBilling (MK2-8014): A configurable concertina view groups invoice ledger entries into expandable rows.
• +AddedBilling (MK2-7134): Quarterly billing schedules support configurable start dates at firm and matter level.
• +AddedBanking (MK2-7138): US cheque payments can be exported to CSV for Positive Pay, with re-export support and audit tracking.
• ↻ChangedClients/Matters (MK2-7052): Early-access entity and matter forms streamline navigation, actions, permissions, and inactive-record handling.
• ✓FixedClients/Matters (MK2-7903): On Hold, Closing, and Closed matters must be reactivated before their details can be changed.
• ✓FixedClients/Matters (MK2-8029): Updated matter permissions take effect immediately without reopening the matter.
• ✓FixedPurchases (MK2-8118): Reversing a payment against a negative supplier purchase no longer reports a false overpayment.
• ✓FixedBilling (MK2-7968): Percentage fee adjustment labels correctly distinguish increases from decreases.
• ✓FixedBilling (MK2-8149): Smokeball invoice filing creates only the required Accounts folder and document.
• ✓FixedSystem (MK2-8021): CMA notification emails include organisation and joint-party client names.