feat: list upcoming events with a create button

The list page now parses the calendar feed and renders each upcoming
event (title, date, place) in chronological order, with a button that
hands the event over to the town hall form.

Sorting, date formatting and the café fallback live in a pure
presentation module rather than in liste.js, which touches the DOM and
cannot be imported under bun test. The seam to the sibling task's
content script lives in transfert.js: a single storage slot, since a
content script running on the town hall site has no way to learn a uid.
The deposit is awaited before opening the tab, otherwise the content
script could read before the write lands.

Test timezone is pinned to Europe/Paris: date formatting is the core
logic here and would otherwise pass only on machines set to Paris.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

extension.test.ts

@@ -21,6 +21,10 @@ describe("manifest.json", () => {
     ]);
   });
 
+  test("demande la permission storage (couture liste → formulaire)", () => {
+    expect(manifest.permissions).toContain("storage");
+  });
+
   test("ne définit PAS default_popup (sinon onClicked devient muet)", () => {
     expect(manifest.action.default_popup).toBeUndefined();
   });