fix: apply code-review findings to import_fruits script and tests

- find_images: verify exact fruit_id prefix (stem-parse before _s0.) to
  prevent cross-fruit image contamination (e.g. mitschurins steals
  mitschurins_fruchtbare images)
- DATA_DIR uses os.path.abspath to handle symlinks / relative invocation
- counts["images"] derived from IMAGE_DIRS constant, not hardcoded keys
- counts["warnings"] incremented on missing-id/name skip (was missing)
- UPSERT preserves existing comment (comment = fruits.comment, not NULL)
- Print summary and rollback moved inside try/except to avoid NameError
- Remove dead XML_PATH constant
- Tests: add tearDown to clean up tmpdir; fix vacuous _tn exclusion test
  to include positive-control _s0 file; add prefix-collision regression test

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

scripts/import_fruits_test.py

@@ -1,4 +1,5 @@
 import os
+import shutil
 import tempfile
 import unittest
 from datetime import date
@@ -127,6 +128,9 @@ class TestFindImages(unittest.TestCase):
         for d in (self.ef_dir, self.bl_dir, self.bau_dir):
             os.makedirs(d)
 
+    def tearDown(self):
+        shutil.rmtree(self.tmpdir, ignore_errors=True)
+
     def _touch(self, path, content=b"img"):
         with open(path, "wb") as f:
             f.write(content)
@@ -149,10 +153,13 @@ class TestFindImages(unittest.TestCase):
         types = [i["image_type"] for i in imgs]
         self.assertIn("tree", types)
 
-    def test_skips_tn_files(self):
+    def test_skips_tn_files_but_finds_s0(self):
+        # _tn file must be excluded; _s0 file must be included (positive control)
         self._touch(os.path.join(self.ef_dir, "adams_apfel_ef_tn.jpg"))
+        self._touch(os.path.join(self.ef_dir, "adams_apfel_ef_s0.jpg"))
         imgs = find_images("adams_apfel", self.tmpdir)
-        self.assertEqual(imgs, [])
+        self.assertEqual(len(imgs), 1)
+        self.assertEqual(imgs[0]["filename"], "adams_apfel_ef_s0.jpg")
 
     def test_returns_empty_when_no_match(self):
         imgs = find_images("unknown_fruit", self.tmpdir)
@@ -173,6 +180,14 @@ class TestFindImages(unittest.TestCase):
         imgs = find_images("abbe_fetel", self.tmpdir)
         self.assertEqual(len(imgs), 3)
 
+    def test_does_not_steal_images_from_fruit_with_longer_id(self):
+        # "mitschurins" must not match "mitschurins_fruchtbare_nda_s0.jpg"
+        self._touch(os.path.join(self.ef_dir, "mitschurins_ef_s0.jpg"))
+        self._touch(os.path.join(self.ef_dir, "mitschurins_fruchtbare_ef_s0.jpg"))
+        imgs = find_images("mitschurins", self.tmpdir)
+        self.assertEqual(len(imgs), 1)
+        self.assertEqual(imgs[0]["filename"], "mitschurins_ef_s0.jpg")
+
 
 if __name__ == "__main__":
     unittest.main()