Add organizing files into Artist/Album/01 Title from their tags

A new Organize tab renames audio files from their tags into a per-pair
naming pattern, by default {artist}/{album}/{track} {title} (album
artist, falling back to artist). Multi-disc albums get a disc prefix
(2-04) or a Disc N folder; names are made safe for Windows/SMB shares.

- Preview first: every rename, files already organized, and files
  skipped with the reason (missing tags, with a button into the tag
  editor; two files resolving to the same name; an existing file).
- Applying re-checks each file against the preview, moves it within its
  library (hardlinks and contents untouched, case-only renames via a
  temporary name, completed on startup after a crash), carries .lrc
  lyrics and folder cover art along, and removes emptied folders. Each
  move is an operation that can be undone; the library is rescanned.
- Optional automatic organizing of the slave, master or both during
  scans (off by default). Dry run applies.
- Scans now recognise a slave file that is a hardlink of a master file
  at a different path as linked ("same file, other path") instead of
  unmatched.

Migration 7 adds the per-pair naming settings.

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

README.md

@@ -83,6 +83,21 @@ tags** buttons. Edits are safe with hardlinks:
 - Each edit is listed in History (old → new values) and can be undone; an in-place edit interrupted by a crash is rolled back on
   startup. Dry run applies.
 
+**Organize (rename files from tags).** The *Organize* tab renames files into one layout, by default
+`{artist}/{album}/{track} {title}` → `Avenged Sevenfold/Nightmare/01 Nightmare.flac` (`{artist}` is the album artist, falling back to
+the artist). Tokens: `{artist}`, `{album}`, `{track}`, `{title}`, `{year}`, `{disc}`, `{track_artist}`, `{genre}`. Multi-disc albums get
+a disc prefix (`2-04 Title`) or a `Disc 2` folder. Names are made safe for Windows/SMB shares (`AC/DC` → `AC-DC`, `Title: Sub` →
+`Title - Sub`).
+
+- **Preview first:** every file with its new name, what is already organized, and what is skipped and why (missing tags, with a
+  *Fix tags* button that opens the tag editor, or two files that would get the same name).
+- Files are only moved within their library, so contents and hardlinks never change. Lyrics (`.lrc`) move with their song, cover art
+  follows when a whole folder moves, and emptied folders are removed.
+- Organizing **both libraries** keeps paths in step. A slave file that is a hardlink of a master file at a different path is still
+  recognised as linked.
+- Each rename is in History and can be undone; the library is rescanned afterwards. Optionally, a pair can organize the slave, the
+  master or both automatically during every scan (off by default). Dry run applies.
+
 **Export.** The Review tab's **Export CSV** button downloads either the current view (filter and search applied) or the entire scan.
 Each row has the match status and type, a recommendation, both paths, where linking would place the file, codec, bitrate, sample rate,
 bit depth and duration for both sides, the quality verdict and any notes. The file opens cleanly in Excel, Numbers and LibreOffice