fix(repository): stretch the Value column in Setting history dialog

The dialog stretched the middle "Setting" column, leaving "Value" stuck at
the ~100px default with no draggable handle (it's the last column next to a
stretch section). Switch to the codebase convention used by the sibling
da12 history dialog: stretch the last column ("Value"), keep sections
Interactive (resizable), and resizeColumnsToContents for sensible initial
widths. Value now fills the space, Setting fits its label, columns resize.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

cim_suite/core/repository/ui/history_dialog.py

@@ -12,7 +12,6 @@ from PySide6.QtWidgets import (
     QDialog,
     QFileDialog,
     QHBoxLayout,
-    QHeaderView,
     QLineEdit,
     QPushButton,
     QTableWidget,
@@ -56,12 +55,16 @@ class SettingHistoryDialog(QDialog):
         self.table.setHorizontalHeaderLabels(_HEADERS)
         self.table.setEditTriggers(QAbstractItemView.EditTrigger.NoEditTriggers)
         self.table.setSelectionBehavior(QAbstractItemView.SelectionBehavior.SelectRows)
-        self.table.horizontalHeader().setSectionResizeMode(
-            1, QHeaderView.ResizeMode.Stretch
-        )
+        # Sections stay Interactive (user-resizable); the last column ("Value")
+        # stretches to fill the remaining width — it's the field being inspected,
+        # so it gets the room, not the middle "Setting" column.
+        self.table.horizontalHeader().setStretchLastSection(True)
         layout.addWidget(self.table)
 
         self._populate(self._rows)
+        # Fit Timestamp/Setting to their content for a sensible initial layout;
+        # the stretched "Value" column then fills whatever space is left.
+        self.table.resizeColumnsToContents()
 
     def _populate(self, rows) -> None:
         self._shown = list(rows)  # what's on screen now; export mirrors this

tests/core/test_repository_dialog.py

@@ -55,6 +55,21 @@ def test_dialog_exports_current_rows_to_xlsx(qtbot, tmp_path):
     assert out.exists() and out.stat().st_size > 0
 
 
+def test_value_column_fills_space_and_columns_are_resizable(qtbot):
+    from PySide6.QtWidgets import QHeaderView
+
+    repo = _repo_with_rows()
+    dlg = SettingHistoryDialog(repo, "MAC1")
+    qtbot.addWidget(dlg)
+    header = dlg.table.horizontalHeader()
+    # The last column ("Value") fills remaining width — NOT the middle "Setting".
+    assert header.stretchLastSection() is True
+    assert header.sectionResizeMode(1) != QHeaderView.ResizeMode.Stretch
+    # Columns stay user-resizable (Interactive), so a long value can be widened.
+    assert header.sectionResizeMode(0) == QHeaderView.ResizeMode.Interactive
+    assert header.sectionResizeMode(1) == QHeaderView.ResizeMode.Interactive
+
+
 def test_export_mirrors_active_filter(qtbot):
     repo = _repo_with_rows()
     dlg = SettingHistoryDialog(repo, "MAC1")