Redesigned return request flow, plus field write-offs and search improvements

The return request flow has been rebuilt. When you submit a return, your notes and reason now travel with the request all the way to support, so you don't have to repeat yourself in a follow-up message.

Field office managers can now write off a restock order that never arrived. Previously, those orders sat open in the queue with no way to close them out. Marking a restock as written off clears it from the active queue and records what happened for audit purposes.

The sidebar now responds to resize dragging with a proper cursor, and clicking the collapsed rail expands it. Orders show a pending state while final pricing calculates, so you see progress instead of a blank line.