- build_field_editor() helper: reusable field row editor shared by
bin editor, bin type dialog (open_component_dialog still uses its own)
- open_bin_editor: tabs (Corners|Fields|Contents), field editor on
Fields tab, content list on Contents tab, save always persists fields
- open_bin_type_dialog: field editor appended below existing form fields
- render_bin_contents / open_bin_content_dialog: content item CRUD
(component ref or free-text name, quantity, notes); add/edit/delete
update all_bins immediately without closing the editor
- bc-cancel / bc-save handlers registered in init()
- bin-content-row CSS
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>