test: assert export_count absent from export state response

Address PR review: add negative assertions so re-introducing the legacy alias fails the suite, and reference PR #60 in the CHANGELOG removal note.

Author: clean6378-max-it

CHANGELOG.md

@@ -19,6 +19,6 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.1.0/).
 
 ### Removed
 
-- `export_count` on `GET /api/export/state` — use `last_export_session_count` (deprecated since policy PR; bundled SPA updated in same release)
+- `export_count` on `GET /api/export/state` — use `last_export_session_count` (deprecated in PR #60 / [deprecation policy](docs/deprecation-policy.md); bundled SPA updated in same release)
 
 [Unreleased]: https://github.com/cppalliance/claude-code-chat-browser/compare/f70505982d435f8b1f754cb18c0c9f65609f11b4...HEAD

tests/test_api_routes.py

@@ -71,6 +71,7 @@ def test_export_state_defaults(client_empty):
     assert resp.status_code == 200
     body = resp.get_json()
     assert "last_export_session_count" in body
+    assert "export_count" not in body
 
 
 def test_bulk_export_empty_projects_returns_422(client_empty):

tests/test_export_api_bulk.py

@@ -86,3 +86,4 @@ def test_export_state_json_fields(isolated_state):
     assert resp.status_code == 200
     body = resp.get_json()
     assert body["last_export_session_count"] == 5
+    assert "export_count" not in body