Tooltips in the Notebooks chooser

From the development repository at e819bc4.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

kokkoja.py

@@ -403,7 +403,8 @@ class Handler(http.server.SimpleHTTPRequestHandler):
     def notebook_request(self, method, path):
         """
         GET /api/notebooks                     the notebooks
-        GET /api/notebooks/<notebook>          the pages of a notebook
+        GET /api/notebooks/<notebook>          the pages of a notebook, and
+                                               when each was last changed
         GET /api/notebooks/<notebook>/<page>   a page
         PUT /api/notebooks/<notebook>/<page>   write a page
         POST /api/notebooks/<notebook>/keep    keep a copy of Current.svg
@@ -460,7 +461,9 @@ class Handler(http.server.SimpleHTTPRequestHandler):
                                 "notebooks": self.listing(self.notebooks, directories=True),
                                 "trash": self.trash is not None})
             elif len(names) == 1:
-                self.send_json({"pages": self.listing(target, directories=False)})
+                pages = self.listing(target, directories=False)
+                self.send_json({"pages": pages,
+                                "changed": {name: int((target / name).stat().st_mtime * 1000) for name in pages}})
             else:
                 self.send_body(target.read_bytes(), "image/svg+xml")
         except FileNotFoundError: