fix(audit): sort milestones, sort JSON export, extract test helper

- Fix milestone section using unsorted repos list
- Apply --sort to --format json output
- Rename _sort_repos to sort_repos (now used by cli.py)
- Extract shared make_repo helper to tests/helpers.py
- Move exporter import to module level in cli.py

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

tests/test_display.py

@@ -4,11 +4,13 @@ from io import StringIO
 
 from rich.console import Console
 
-from gitea_dashboard.collector import RepoData
 from gitea_dashboard.display import (
     render_dashboard,
+    sort_repos,
 )
 
+from tests.helpers import make_repo as _make_repo
+
 
 def _make_console():
     """Create a console that captures output for testing.
@@ -20,33 +22,6 @@ def _make_console():
     return Console(file=buf, force_terminal=True, width=120, highlight=False), buf
 
 
-def _make_repo(
-    name="my-repo",
-    full_name="admin/my-repo",
-    description="A repo",
-    open_issues=3,
-    is_fork=False,
-    is_archived=False,
-    is_mirror=False,
-    latest_release=None,
-    milestones=None,
-    last_commit_date=None,
-):
-    """Build a RepoData for testing."""
-    return RepoData(
-        name=name,
-        full_name=full_name,
-        description=description,
-        open_issues=open_issues,
-        is_fork=is_fork,
-        is_archived=is_archived,
-        is_mirror=is_mirror,
-        latest_release=latest_release,
-        milestones=milestones if milestones is not None else [],
-        last_commit_date=last_commit_date,
-    )
-
-
 class TestRenderDashboardTable:
     """Test the main repos table rendering."""
 
@@ -290,35 +265,32 @@ class TestColorizeMilestoneDue:
 
 
 class TestSortRepos:
-    """Test _sort_repos function."""
+    """Test sort_repos function."""
 
     def test_sort_by_name(self):
         """Sorts alphabetically by name (case-insensitive)."""
-        from gitea_dashboard.display import _sort_repos
 
         repos = [
             _make_repo(name="Charlie"),
             _make_repo(name="alpha"),
             _make_repo(name="Bravo"),
         ]
-        result = _sort_repos(repos, "name")
+        result = sort_repos(repos, "name")
         assert [r.name for r in result] == ["alpha", "Bravo", "Charlie"]
 
     def test_sort_by_issues(self):
         """Sorts by issues count descending."""
-        from gitea_dashboard.display import _sort_repos
 
         repos = [
             _make_repo(name="low", open_issues=1),
             _make_repo(name="high", open_issues=10),
             _make_repo(name="mid", open_issues=5),
         ]
-        result = _sort_repos(repos, "issues")
+        result = sort_repos(repos, "issues")
         assert [r.name for r in result] == ["high", "mid", "low"]
 
     def test_sort_by_release(self):
         """Sorts by release date descending; repos without release last."""
-        from gitea_dashboard.display import _sort_repos
 
         repos = [
             _make_repo(name="no-rel", latest_release=None),
@@ -331,17 +303,16 @@ class TestSortRepos:
                 latest_release={"tag_name": "v2.0", "published_at": "2026-03-01T00:00:00Z"},
             ),
         ]
-        result = _sort_repos(repos, "release")
+        result = sort_repos(repos, "release")
         assert [r.name for r in result] == ["new", "old", "no-rel"]
 
     def test_sort_by_activity(self):
         """Sorts by last commit date descending; repos without commit last."""
-        from gitea_dashboard.display import _sort_repos
 
         repos = [
             _make_repo(name="inactive", last_commit_date=None),
             _make_repo(name="old-commit", last_commit_date="2025-06-01T00:00:00Z"),
             _make_repo(name="recent", last_commit_date="2026-03-10T00:00:00Z"),
         ]
-        result = _sort_repos(repos, "activity")
+        result = sort_repos(repos, "activity")
         assert [r.name for r in result] == ["recent", "old-commit", "inactive"]