fix: address 3 code review findings (round 10)

- immich_api: use 'or []' instead of .get("people", []) in get_people
  so {"people": null} responses (some Immich versions with zero people
  enrolled) return [] rather than None; .get() default only fires when
  the key is absent, not when its value is null
- embeddings: log OSError from os.dup2 restore at DEBUG rather than
  silently swallowing it; if a C extension (CUDA/onnxruntime) invalidates
  the saved fd, the restore fails silently and stdout stays wired to
  /dev/null — logging makes the event observable without changing the
  swallow-and-continue semantics
- cache: remove MemoryError re-raise from EmbeddingCache.get(); a cache
  read OOM aborted the entire diversity-selection batch for the person
  rather than falling back to a fresh embedding computation, which is
  the more appropriate OOM gate; broadening back to except Exception
  restores the pre-round-5 fallback behavior

winnow/cache.py

@@ -75,8 +75,6 @@ class EmbeddingCache:
         if os.path.exists(path):
             try:
                 return np.load(path)
-            except MemoryError:
-                raise
             except Exception:
                 return None
         return None

winnow/embeddings.py

@@ -45,8 +45,8 @@ def _suppress_output():
         if saved_out is not None:
             try:
                 os.dup2(saved_out, 1)
-            except OSError:
-                pass
+            except OSError as e:
+                logger.debug("_suppress_output: failed to restore stdout fd: %s", e)
             finally:
                 try:
                     os.close(saved_out)
@@ -55,8 +55,8 @@ def _suppress_output():
         if saved_err is not None:
             try:
                 os.dup2(saved_err, 2)
-            except OSError:
-                pass
+            except OSError as e:
+                logger.debug("_suppress_output: failed to restore stderr fd: %s", e)
             finally:
                 try:
                     os.close(saved_err)

winnow/immich_api.py

@@ -61,7 +61,7 @@ def get_people() -> list[dict]:
         if not isinstance(data, dict):
             logger.error("Unexpected response shape from Immich /people: %r", type(data))
             return []
-        return data.get("people", [])
+        return data.get("people") or []
     except (requests.RequestException, ValueError, AttributeError) as e:
         logger.error("Failed to fetch people from Immich: %s", e)
         return []