Improve entries page and latest changes panel, units on events and timeline

lib/components/pages/loco_timeline/timeline_grid.dart

@@ -577,7 +577,7 @@ class _TimelineModel {
           _ValueSegment(
             start: start,
             end: end,
-            value: entry.valueLabel,
+            value: _formatValueWithUnits(entry),
             entry: entry,
           ),
         );
@@ -680,6 +680,53 @@ class _TimelineModel {
   }
 }
 
+String _formatValueWithUnits(LocoAttrVersion entry) {
+  final raw = entry.valueLabel;
+  final code = entry.attrCode.toLowerCase();
+  final lowerRaw = raw.toLowerCase();
+  // Avoid double-appending if units already present.
+  final hasUnits = lowerRaw.contains('mm') ||
+      lowerRaw.contains('tonne') ||
+      lowerRaw.contains('kph') ||
+      lowerRaw.contains('mph');
+
+  double? asNumber = double.tryParse(raw);
+  String formatNumber(double value) {
+    if (value % 1 == 0) return value.toStringAsFixed(0);
+    return value.toStringAsFixed(2);
+  }
+
+  switch (code) {
+    case 'height':
+    case 'length':
+    case 'width':
+    case 'track_gauge':
+      if (hasUnits) return raw;
+      return asNumber != null ? '${formatNumber(asNumber)} mm' : '$raw mm';
+    case 'weight':
+      if (hasUnits) return raw;
+      return asNumber != null ? '${formatNumber(asNumber)} tonnes' : '$raw tonnes';
+    case 'power':
+      if (hasUnits) return raw;
+      return asNumber != null ? '${formatNumber(asNumber)} kW' : '$raw kW';
+    case 'tractive_effort':
+      if (hasUnits) return raw;
+      return asNumber != null ? '${formatNumber(asNumber)} kN' : '$raw kN';
+    case 'max_speed':
+      if (hasUnits) return raw;
+      if (asNumber != null) {
+        // Stored as kph.
+        final formatted = asNumber % 1 == 0
+            ? asNumber.toStringAsFixed(0)
+            : asNumber.toStringAsFixed(1);
+        return '$formatted kph';
+      }
+      return '$raw kph';
+    default:
+      return raw;
+  }
+}
+
 class _AxisSegment {
   final DateTime start;
   final DateTime end;
@@ -742,7 +789,15 @@ class _RowCell {
         color: Colors.transparent,
       );
     }
-    final displayStart = _formatDate(seg.start) ?? '';
+    final entry = seg.entry;
+    String displayStart = '';
+    if (entry != null) {
+      if ((entry.maskedValidFrom ?? '').trim().isNotEmpty) {
+        displayStart = entry.maskedValidFrom!.trim();
+      } else if (entry.validFrom != null) {
+        displayStart = _formatDate(entry.validFrom) ?? '';
+      }
+    }
     return _RowCell(
       value: seg.value,
       rangeLabel: displayStart,