Tabular structure is preserved — four aligned columns: name · venact type · physical type · expression.
Clicking an OUTPUT column enables edit mode. Below: current vs proposed; the middle
row (full_name) is in edit mode in both.
Columns: name · venact type · physical type · expression — aligned across all rows.
Type display (out of scope of this change, just the rule): venact type = code when known, else ?;
physical type = value when known, else light unknown — never blank. Only name + expression are editable.
unknown (no input for now); when known it shows the value normally — never blank. (Venact type follows the same idea: code when known, else ?.)expression placeholder is a lighter gray than the current default.