feat(auth): make OAuth credentials user-specific via UserIntegration records

Setup pages now accept an integration_id query param to save OAuth
credentials to the user's personal UserIntegration record instead
of global settings. The integrations dashboard shows an "Authorize"
button for OAuth types (Dropbox, Google Drive, OneDrive) that need
credentials.

Co-authored-by: christianlouis <361235+christianlouis@users.noreply.github.com>

tests/test_views_onedrive.py

@@ -26,3 +26,19 @@ class TestOnedriveViews:
         """Test the OneDrive OAuth callback with auth code."""
         response = client.get("/onedrive-callback?code=test_code")
         assert response.status_code == 200
+
+    def test_onedrive_setup_page_with_integration_id(self, client):
+        """Test the OneDrive setup page accepts integration_id query param."""
+        response = client.get("/onedrive-setup?integration_id=77")
+        assert response.status_code == 200
+        # The template should store the integration_id for per-user OAuth flow
+        assert b"oauth_integration_id" in response.content
+        assert b"77" in response.content
+
+    def test_onedrive_setup_page_without_integration_id(self, client):
+        """Test the OneDrive setup page works without integration_id (global flow)."""
+        response = client.get("/onedrive-setup")
+        assert response.status_code == 200
+        body = response.text
+        assert "oauth_integration_id" in body
+        assert 'const integrationId = ""' in body