fix(records): include _Measure as visible column in records mode (improvise-rbv)

The records mode column filter excluded all categories starting with '_',
which hid _Measure. Changed to explicitly exclude only _Index and _Dim,
making _Measure visible as a data column. Updated the blank-model editing
test to reflect the new column order (_Measure first, Value last).

Made-with: Cursor

src/ui/app.rs

@@ -744,7 +744,8 @@ mod tests {
 
     /// Regression: editing the first row in a blank model's records view
     /// should persist the typed value even though plain records mode does not
-    /// use drill state.
+    /// use drill state. With _Measure as the first column, `o` lands on it;
+    /// type a measure name, Tab to Value, type the number, Enter to commit.
     #[test]
     fn edit_record_row_in_blank_model_persists_value() {
         use crate::model::cell::CellKey;
@@ -753,15 +754,30 @@ mod tests {
 
         app.handle_key(KeyEvent::new(KeyCode::Char('R'), KeyModifiers::NONE))
             .unwrap();
+        // `o` adds a record row and enters edit at (0, 0) = _Measure column
         app.handle_key(KeyEvent::new(KeyCode::Char('o'), KeyModifiers::NONE))
             .unwrap();
+        // Type a measure name
+        app.handle_key(KeyEvent::new(KeyCode::Char('R'), KeyModifiers::NONE))
+            .unwrap();
+        app.handle_key(KeyEvent::new(KeyCode::Char('e'), KeyModifiers::NONE))
+            .unwrap();
+        app.handle_key(KeyEvent::new(KeyCode::Char('v'), KeyModifiers::NONE))
+            .unwrap();
+        // Tab to commit _Measure and move to Value column
+        app.handle_key(KeyEvent::new(KeyCode::Tab, KeyModifiers::NONE))
+            .unwrap();
+        // Type the value
         app.handle_key(KeyEvent::new(KeyCode::Char('5'), KeyModifiers::NONE))
             .unwrap();
+        // Enter to commit
         app.handle_key(KeyEvent::new(KeyCode::Enter, KeyModifiers::NONE))
             .unwrap();
 
         assert_eq!(
-            app.model.get_cell(&CellKey::new(vec![])),
+            app.model.get_cell(&CellKey::new(vec![
+                ("_Measure".to_string(), "Rev".to_string()),
+            ])),
             Some(&crate::model::cell::CellValue::Number(5.0)),
             "editing a synthetic row in plain records mode should write the value"
         );

src/view/layout.rs

@@ -160,7 +160,7 @@ impl GridLayout {
         let cat_names: Vec<String> = model
             .category_names()
             .into_iter()
-            .filter(|c| !c.starts_with('_'))
+            .filter(|c| *c != "_Index" && *c != "_Dim")
             .map(String::from)
             .collect();
         let mut col_items: Vec<AxisEntry> = cat_names
@@ -698,6 +698,35 @@ mod tests {
         assert_eq!(dim, "Region");
     }
 
+    /// Regression test for improvise-rbv: records mode should include _Measure
+    /// as a _Dim column so the measure name is visible per-record, and "Value"
+    /// must remain the last column.
+    #[test]
+    fn records_mode_includes_measure_in_dim_columns() {
+        let mut m = records_model();
+        let v = m.active_view_mut();
+        v.set_axis("_Index", Axis::Row);
+        v.set_axis("_Dim", Axis::Column);
+        let layout = GridLayout::new(&m, m.active_view());
+        assert!(layout.is_records_mode());
+        let cols: Vec<String> = (0..layout.col_count())
+            .map(|i| layout.col_label(i))
+            .collect();
+        assert!(
+            cols.contains(&"_Measure".to_string()),
+            "records mode should include _Measure column; got {:?}",
+            cols
+        );
+        assert!(cols.contains(&"Region".to_string()));
+        assert!(cols.contains(&"Value".to_string()));
+        assert_eq!(
+            cols.last().unwrap(),
+            "Value",
+            "Value must be the last column so cursor defaults land on it; got {:?}",
+            cols
+        );
+    }
+
     fn coord(pairs: &[(&str, &str)]) -> CellKey {
         CellKey::new(
             pairs