Fix: make pipe table prettifier apply visible alignment changes

Treat internal spacing changes as real formatting differences and normalize separator padding so table prettification is applied consistently. Save files before running pre-commit fixers from the extension so results match editor state.

book/tools/scripts/utilities/prettify_pipe_tables.py

@@ -159,7 +159,9 @@ def prettify_table(table_lines: list[str]) -> list[str]:
             # Build separator row
             sep_cells = [make_separator_cell(alignments[j], col_widths[j]) 
                         for j in range(num_cols)]
-            result.append('|' + '|'.join(sep_cells) + '|')
+            # Keep separator visually consistent with data rows by adding
+            # single-space padding around each separator cell.
+            result.append('| ' + ' | '.join(sep_cells) + ' |')
         else:
             # Build data row with padding
             if row_idx < len(rows):
@@ -236,14 +238,13 @@ def find_pipe_tables(content: str) -> list[tuple[int, int, list[str]]]:
 
 
 def tables_are_equal(original: list[str], prettified: list[str]) -> bool:
-    """Check if two tables are equivalent (ignoring whitespace differences)."""
+    """Check if two tables are textually identical for formatting purposes."""
     if len(original) != len(prettified):
         return False
     for orig, pretty in zip(original, prettified):
-        # Normalize: strip and collapse multiple spaces
-        orig_norm = ' '.join(orig.split())
-        pretty_norm = ' '.join(pretty.split())
-        if orig_norm != pretty_norm:
+        # Ignore trailing whitespace-only differences, but keep internal
+        # spacing significant so alignment changes are detected.
+        if orig.rstrip() != pretty.rstrip():
             return False
     return True