fix: force-fetch repo details so newly enabled features show up

The Anonymize form used the cached RepositoryModel for hasPage,
defaultBranch, etc. — so enabling GitHub Pages (or changing the
default branch) on the source after first cache wouldn't reflect in
the UI, leaving the GitHub Pages checkbox grayed out.

Pass force=1 when loading the form's repo details so the backend
re-queries the GitHub API once. The cost is a single GET /repos/...
call per form load.

Fixes #364.

public/script/app.js

@@ -1365,8 +1365,11 @@ angular
         const o = parseGithubUrl($scope.sourceUrl);
         try {
           resetValidity();
+          // force=1 so newly enabled features (e.g. GitHub Pages — see
+          // #364) are reflected without waiting for the cached metadata to
+          // expire. The endpoint hits the GitHub API once.
           const res = await $http.get(`/api/repo/${o.owner}/${o.repo}/`, {
-            params: { repositoryID: $scope.repositoryID },
+            params: { repositoryID: $scope.repositoryID, force: "1" },
           });
           $scope.details = res.data;
           if (!$scope.repoId) {