feat: add theme and fonts to lexicon

lexicons/space/litenote/note.json

@@ -32,6 +32,20 @@
           "createdAt": {
             "type": "string",
             "format": "datetime"
+          },
+          "fontFamily": {
+            "type": "string",
+            "description": "Font family name available from Coollabs.",
+            "maxLength": 200
+          },
+          "fontSize": {
+            "type": "integer",
+            "description": "Font size in points. Recommended range: 9–21, but clients may allow larger sizes for accessibility."
+          },
+          "theme": {
+            "type": "string",
+            "description": "Display theme for the note.",
+            "knownValues": ["light", "dark"]
           }
         }
       }