fix(chart): improve error handling and color variety

- Add quotaExceeded flag to response for better error UX
- Show dedicated quota exceeded state with upgrade button
- Improve AI prompt to better detect data patterns
- Add chart type-specific colors (blue, indigo, emerald, violet, etc.)
- Replace generic primary/10 colors with varied accent colors

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

memento-note/locales/en.json

@@ -2658,5 +2658,28 @@
     "emptyState": "No versions available",
     "selectVersion": "Select a version to preview its content",
     "currentVersion": "current"
+  },
+  "graphView": {
+    "title": "Graph View",
+    "notesCount": "{count} notes",
+    "connectionsCount": "{count} connections",
+    "globalView": "Fit to View",
+    "searchPlaceholder": "Filter...",
+    "noNotesFound": "No notes found",
+    "notebooks": "Notebooks",
+    "resetFilter": "Reset",
+    "relationshipTypes": "Relationship Types",
+    "connections": "{count} connection",
+    "connectionsPlural": "{count} connections",
+    "preview": {
+      "openNote": "Open note",
+      "emptyNote": "Empty note",
+      "tags": "Tags",
+      "noTags": "No tags",
+      "words": "{count} words",
+      "chars": "{count} chars",
+      "created": "Created on",
+      "updated": "Updated on"
+    }
   }
 }