Add renaming slave folders to the master's spelling

The "N folders are named differently" warning now offers to rename the
slave folders to match the master, marked as the recommended first step
after a scan (also linked from the dashboard card).

- A preview lists each rename with the differing characters highlighted;
  renames are selectable, and conflicts (the slave already has a folder
  with the master's name, symlinks, the quarantine) are skipped with a
  reason.
- Only renames the server computes itself are applied; a request can
  only narrow them down, never name arbitrary paths. Only slave folders
  are renamed.
- Case-only renames go through a temporary name so they also work on
  case-insensitive filesystems; a rename interrupted by a crash is
  completed on startup (the folder is never removed).
- Renaming everything repeats until folders revealed inside renamed ones
  (an album under a renamed artist) are fixed too, then rescans.
- Each rename is an operation in History that can be undone (which also
  rescans). Dry run records renames as planned.

Also fixes the Review list not refreshing after a job that started and
finished between two status polls, and logs the new path of operations.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

README.md

@@ -57,6 +57,13 @@ codec-weighted bitrate (Opus and AAC count for more per kbps than MP3). You then
   libraries share the better file.
 - **Ignore.** The pair is hidden from review until you un-ignore it.
 
+**Rename folders to match (recommended first step).** When a scan finds slave folders that are the same as a master folder with a
+different spelling (`City Of Evil` vs `City of Evil`, `AC-DC` vs `AC_DC`, look-alike hyphens), the warning offers to rename the slave
+folders to the master's spelling so their songs match by path. Do this right after a scan, before reviewing matches. A preview lists
+every rename with the differences highlighted; conflicts (the slave already has a folder with the master's name) are skipped with the
+reason. Only slave folders are renamed, nested folders revealed by a rename are handled in the same run, every rename appears in
+History and can be undone, and the library is rescanned afterwards.
+
 **Bulk review.** Switch the Review list from *Songs* to *Albums* to see one row per album (disc folders are folded in), with
 counts of upgrades, identical files, songs where the master is lower quality and approximate matches. Tick whole albums, or expand an
 album and tick individual songs, then **Link**, **Use slave copies as master**, **Ignore** or **Un-ignore** them in one go. Before