Scope editing is now responsive

Fixed UI freeze when editing work areas and improved estimate matching reliability

Bug Fixes

Closing the Edit Work Area sheet no longer triggers a page refresh, eliminating a ~500ms UI freeze when editing scope. Assessment fields now save changes with a 500ms debounce instead of on every keystroke, preventing form lockup during rapid input.

The contents estimate pipeline now falls back correctly when no direct match is found, selecting the cheapest available option instead of failing entirely. Error messages have been cleaned up for clarity.