#912: Empty Folder Cleaner reads its opt-in from the right config key

The #891 'also remove image/sidecar-only folders' toggle never worked. Job settings are
persisted as a nested dict under repair.jobs.<id>.settings (RepairWorker.set_job_settings),
but the scan read flat keys — repair.jobs.empty_folder_cleaner.remove_residual_files — which
never matched, so it always fell back to the False default and skipped every image/.lrc-only
folder. (remove_junk_files had the same mismatch but its default is True, which is why only the
truly-empty 'deleted' folder kept showing up.) Now reads from .settings like get_job_config /
lossy_converter do.

The pure dir_is_removable logic was already correct + tested; the bug was purely the config
read in scan(), which had no test. Added two scan-level regression tests driving the real
JobContext + a config that stores the toggle the way the UI does.

core/repair_jobs/empty_folder_cleaner.py

@@ -91,13 +91,19 @@ class EmptyFolderCleanerJob(RepairJob):
         ignore_disposable = False
         try:
             if context.config_manager:
-                ignore_junk = bool(context.config_manager.get(
-                    'repair.jobs.empty_folder_cleaner.remove_junk_files', True))
-                # #891: also clear folders left holding only images / .lrc / sidecars
-                # (what a reorganize leaves behind). Opt-in — default off.
-                ignore_disposable = bool(context.config_manager.get(
-                    'repair.jobs.empty_folder_cleaner.remove_residual_files', False))
-        except Exception:  # noqa: S110 — setting read is best-effort; defaults to True
+                # #912: job settings are persisted as a nested dict under
+                # `repair.jobs.<id>.settings` (see RepairWorker.set_job_settings / get_job_config).
+                # The old flat-key reads ('repair.jobs.empty_folder_cleaner.remove_residual_files')
+                # never matched what the UI saves, so the #891 opt-in toggle silently did nothing —
+                # the scan always fell back to the False default and skipped every image/.lrc folder.
+                job_settings = context.config_manager.get(
+                    'repair.jobs.empty_folder_cleaner.settings', {}) or {}
+                if isinstance(job_settings, dict):
+                    ignore_junk = bool(job_settings.get('remove_junk_files', True))
+                    # #891: also clear folders left holding only images / .lrc / sidecars
+                    # (what a reorganize leaves behind). Opt-in — default off.
+                    ignore_disposable = bool(job_settings.get('remove_residual_files', False))
+        except Exception:  # noqa: S110 — setting read is best-effort; defaults to junk-only
             pass
 
         flagged = set()   # dir paths we'd remove → a parent sees them as "gone"

tests/test_empty_folder_cleaner.py

@@ -6,7 +6,10 @@ from __future__ import annotations
 
 import os
 
-from core.repair_jobs.empty_folder_cleaner import dir_is_removable, remove_empty_folder, is_junk
+from core.repair_jobs.base import JobContext
+from core.repair_jobs.empty_folder_cleaner import (
+    EmptyFolderCleanerJob, dir_is_removable, is_junk, remove_empty_folder,
+)
 
 
 # ── pure decision ───────────────────────────────────────────────────────────
@@ -120,3 +123,51 @@ def test_apply_residual_opt_still_refuses_real_content(tmp_path):
                               remove_disposable=True, root=str(root), **_fx())
     assert res['removed'] is False and d.exists()
     assert (d / 'booklet.pdf').exists() and (d / 'cover.jpg').exists()  # nothing deleted
+
+
+# ── #912: scan() must read the opt-in from where the UI SAVES it ─────────────
+class _Cfg:
+    """Mimics ConfigManager: job settings live as a nested dict under
+    `repair.jobs.<id>.settings` (RepairWorker.set_job_settings writes there)."""
+
+    def __init__(self, settings):
+        self._settings = settings
+
+    def get(self, key, default=None):
+        if key == 'repair.jobs.empty_folder_cleaner.settings':
+            return self._settings
+        return default
+
+
+def _run_scan(tmp_path, settings):
+    root = tmp_path / 'lib'; root.mkdir()
+    res_dir = root / 'Artist' / 'Old Album'; res_dir.mkdir(parents=True)
+    (res_dir / 'cover.jpg').write_text('img')       # image + lyric only — the #912 case
+    (res_dir / 'lyrics.lrc').write_text('la')
+    keep = root / 'Artist2' / 'Real Album'; keep.mkdir(parents=True)
+    (keep / 'song.flac').write_text('audio')        # has audio — must never be flagged
+
+    flagged = []
+    ctx = JobContext(
+        db=None, transfer_folder=str(root), config_manager=_Cfg(settings),
+        create_finding=lambda **kw: (flagged.append(kw.get('file_path')), True)[1],
+    )
+    EmptyFolderCleanerJob().scan(ctx)
+    return str(res_dir), str(keep), set(flagged)
+
+
+def test_scan_flags_residual_folder_when_opt_in_saved_under_settings(tmp_path):
+    # The toggle is stored at repair.jobs.<id>.settings.remove_residual_files. The scan must
+    # read it from THERE — the old flat-key read missed it, so the option did nothing (#912).
+    res_dir, keep, flagged = _run_scan(
+        tmp_path, {'remove_junk_files': True, 'remove_residual_files': True})
+    assert res_dir in flagged          # the cover.jpg + .lrc folder is now found
+    assert keep not in flagged         # the audio folder is never touched
+
+
+def test_scan_keeps_residual_folder_when_opt_off(tmp_path):
+    # Opt-off preserves the conservative default: an image/.lrc folder is left alone.
+    res_dir, keep, flagged = _run_scan(
+        tmp_path, {'remove_junk_files': True, 'remove_residual_files': False})
+    assert res_dir not in flagged
+    assert keep not in flagged