Fields: table cells keep stored values, UPDATEFIELD reaches blocks and tables, measured shading box

Table cell fields show their stored value; only formula cells evaluate
live. UPDATEFIELD on a block reference also updates the fields of its
block definition, and on a table the fields of its cells; a changed
table cell text redraws the table. The FIELDDISPLAY box is placed from
the text layout (MTEXT layout cells, TEXT / attribute pen advances) and
spans 0.345 text heights below the baseline to 1.19 above it.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src/entities/table.rs

@@ -646,7 +646,7 @@ fn content_display_value(
 ) -> String {
     if let Some(handle) = content.field_handle {
         if let Some(value) =
-            crate::entities::field::resolve_handle(document, handle, table.common.handle)
+            crate::entities::field::cell_text(document, handle, table.common.handle)
         {
             return value;
         }