Resolve uploaded image references for prompt enhancement

dev/test_router_coordination.py

@@ -3,6 +3,7 @@ import json
 import os
 import sys
 import threading
+import tempfile
 import unittest
 from pathlib import Path
 from unittest.mock import patch
@@ -25,6 +26,14 @@ class CoordinationTests(unittest.TestCase):
         with self.assertRaisesRegex(RuntimeError, 'rewritten_prompt'):
             router._parse_prompt_enhancer_result('{"wh_ratio":"1:1"}')
 
+    def test_image_data_url_resolves_volume_relative_reference(self):
+        with tempfile.TemporaryDirectory() as directory, \
+             patch.object(router, 'IMAGE_DIR', directory):
+            path = Path(directory) / '.edit-reference.ref'
+            path.write_bytes(b'\x89PNG\r\n\x1a\ncontent')
+            result = router._image_data_url(path.name)
+        self.assertTrue(result.startswith('data:image/png;base64,'))
+
     def test_mode_uses_one_consistent_controller_snapshot(self):
         with patch.object(router, 'PROFILE_CONTROL_URL', 'http://controller'), \
              patch.object(router, '_profile_controller_request', return_value={