Full correctness check against the docs: safer writes, reverts and texts

Safety
- Writes are serialized (Workspace.lock): two background jobs rebuilding one
  package (a sound and its subtitle applied side by side) lost an edit.
- A store copies a bank file or package as "original" only if it matches the
  shipped catalog (Workspace.unoriginal_files: in-memory sounds, bank copies of
  voice lines, subtitles); the editor refuses to switch stores while changes
  are applied. A second store could otherwise resurrect a reverted sound.
- Mod import in the editor asks before overwriting files changed outside the
  tool (it forced silently).
- Revert all in the editor reverts texts too; the uninstaller counts text
  edits before offering to delete the store.
- ackit restore-backup: the full-backup restore decisions.md described; it
  keeps the sounds of WADs without a full copy recorded.
- build_catalog also stops when a subtitle differs from the catalog.

Languages and texts
- Game.language() returns languages without voices (JPN, RUS, ...) and
  Game.voice_archive() their INT voices; ackit text --lang JPN works.
- Menu lookups parse one cached file (find & replace: minutes -> ms).
- Subtitles decode cp1252 as Windows does: the UTF-8-in-cp1252 line
  Speech_TAPE_J_Answer_1_00 (KOR/POL/POR/RUS) is written back byte-for-byte;
  SUB_KOR/SUB_RUS rebuilt from the original game (only those rows changed).
- Mods exported while another language is loaded keep name and line.

Other fixes
- Down-mix folds extra channels in at -3 dB (a 5.1 centre voice was dropped).
- e2e_editor no longer overwrites the user's settings.json; kill_game waits
  for the game to exit before reverts.
- Recorder handles Int32/UInt8 input and split frames; package block cache
  locked; conflict messages, CLI help examples, stale docstrings and doc
  references fixed; tests no longer read this PC's game language.

Docs (decisions, user guide, README, subtitles.md, banks.md, catalog README,
REPORT, NOTES, CLAUDE.md) updated; check_docs: 102 claims match. 148 tests;
e2e_features 9/9, e2e_editor and verify PASS; game original afterwards.

docs/user-guide.md

@@ -58,8 +58,9 @@ the same line and are changed and reverted together.
 
 ## Listen
 The editor under the list shows the selected sound in three columns side by side (drag the dividers to
-resize them): **Listen**, **Replace** and **Subtitle**. Select a row and press **Space** (or double-click) to
-play the original. Each column ends with its own buttons on one line. In **Listen**:
+resize them): **Listen**, **Replace** and **Subtitle**. Select a row and press **Space** to play the original
+(once a replacement is loaded, Space plays the replacement; Space again stops), or double-click it. Each column
+ends with its own buttons on one line. In **Listen**:
 - **Original** / **Installed** play the game's original and what is currently in the game; **Stop** (Esc).
   Click on a waveform to play from that point.
 - Above them: **A/B** (switch between the original and your replacement at the same position, to compare),
@@ -82,14 +83,22 @@ than the original, since the game may cut it off.
 
 ## Undo
 - **Revert** in the editor puts that sound back exactly.
-- Right-click rows → **Revert selected**; toolbar **Revert all** puts every original back.
+- Right-click rows → **Revert selected**; toolbar **Revert all** puts every original back: all sounds,
+  subtitles and menu texts you changed, in every language.
 - Originals are kept in your user data folder (`%APPDATA%\UnheardCity` on Windows,
   `~/.local/share/unheardcity` on Linux), so reverting works after updating or reinstalling the app too.
   Uninstalling keeps this folder; use **Revert all** before uninstalling if you want the game back to original.
   Before the first change to a game file, a full copy of it is kept there too: optional for the WAD archives
-  (Settings), always for soundbanks, packages and text files (they are rebuilt from that copy).
+  (Settings), always for soundbanks, packages and text files (they are rebuilt from that copy). Only files the
+  game ships unchanged are copied; a file another tool (or another originals store) has changed is reported as
+  *changed outside this tool* first.
+- The originals of your changes are only in the store that made them, so the store folder (Settings) cannot be
+  changed while changes are applied: use **Revert all** first.
 - If Steam "Verify integrity of game files" or an update undoes your changes, a bar offers **Re-apply my
   changes** or **Forget them**. Do not use "verify" to undo mods; use Revert all.
+- If the store folder itself is damaged, the full copies can still be put back with the command-line toolkit
+  that Unheard City is built on (`ackit restore-backup`, see the project README; not part of the editor
+  download).
 
 ## Subtitles
 The **Subtitles** tab lists the subtitle of every speech line in the selected language (see *Language*).
@@ -123,6 +132,7 @@ Click the **★** column to mark favorites. These are stored in your user data f
 - **Export mod…**: choose which changed sounds and texts to include and save a `.acmod` file (the exact game
   data plus the audio, so it also works for another language whose original has a different size).
 - **Import mod…**: shows which sounds match this game, then installs them. You can revert them like any change.
+  If a sound or text the mod replaces was changed outside the editor, you are asked before it is overwritten.
 - Changed subtitles and menu texts are exported and imported with the sounds (listed as *Text*); a text stays
   in its language (a French subtitle edit changes the French subtitle).
 - In another language, voice lines are matched by the game's own identity of the line, so the same line is
@@ -131,7 +141,8 @@ Click the **★** column to mark favorites. These are stored in your user data f
 
 ## Settings
 ![Settings](img/settings.png)
-Game folder, where originals are kept, the full-backup option and the playback device. The recording device
+Game folder, where originals are kept (changeable only while nothing is modified), the full-backup option and
+the playback device. The recording device
 is chosen next to the Record button. **Background**: show or hide the Arkham City wallpaper behind the filter
 panel; **Background strength**: how visible it is (10 % by default).
 The editor panel opens tall enough to show all its controls; drag the divider above it to change that.