feat: Add body property to Note class

Adds a new `body` property to the `Note` class, allowing users to easily access the note's body content. The property extracts the body from the note's content, splitting it at the first newline. This improves the usability and clarity of the `Note` class.

lib/models.py

@@ -228,24 +228,35 @@ def _title(self):
             content = self._content
         except Exception:
             return CONFIG.SIMPLENOTE_DEFAULT_NOTE_TITLE
-        return self.get_title(content)
+        title, _ = self.get_title_body(content)
+        return title
 
     @property
     def title(self):
         try:
             content = self.d.content
         except Exception:
             return CONFIG.SIMPLENOTE_DEFAULT_NOTE_TITLE
-        return self.get_title(content)
+        title, _ = self.get_title_body(content)
+        return title
+
+    @property
+    def body(self) -> str:
+        _, body = self.get_title_body(self.d.content)
+        return body
 
     @staticmethod
-    def get_title(content: str) -> str:
-        index = content.find("\n")
-        if index > -1:
-            title = content[:index]
+    def get_title_body(content: str) -> tuple[str, str]:
+        if not isinstance(content, str):
+            return CONFIG.SIMPLENOTE_DEFAULT_NOTE_TITLE, "empty body"
+        _content = content.split("\n", 1)
+        title, body = CONFIG.SIMPLENOTE_DEFAULT_NOTE_TITLE, "empty body"
+        if len(_content) == 1:
+            title = _content[0] or title
         else:
-            title = content or CONFIG.SIMPLENOTE_DEFAULT_NOTE_TITLE
-        return title
+            title = _content[0] or title
+            body = _content[1] or body
+        return title, body
 
     @property
     def _filename(self) -> str: