README and TODO: say only what the code does for records it cannot decrypt

A file whose copy in another album decrypted is stored from that copy, and
the album where it does not decrypt neither links nor lists it. Only a run
without --json prints the line for an album. The exit-code and read-command
sentences no longer cover that file, and the failures.json sentence covers
only files in the backup's scope.

Model: opus-5-5

TODO.md

@@ -25,16 +25,18 @@ declares one.
 
 # Completed Steps
 
-- 2026-10-13: An album or file quak cannot decrypt, or whose metadata is not
+- 2026-10-14: An album or file quak cannot decrypt, or whose metadata is not
   JSON, no longer fails the refresh, so one bad record no longer stops
   `quak backup` from storing anything (issue 181). The refresh leaves it out, an
   album with its files, and the library keeps it with the reason in
-  `metadata.json` until the server sends a copy that decrypts or deletes it. The
-  backup stores every other file, records each such file in `failures.json` with
-  an error starting `could not be decrypted:`, prints one line naming each such
-  album's ID, lists those IDs in `undecryptableAlbums`, and exits 1 while any
-  remain. A file whose copy in another album decrypts is backed up as usual. The
-  read commands answer from what decrypted.
+  `metadata.json` until the server sends a copy that decrypts or deletes it.
+  `quak backup` stores every other file, records each such file in
+  `failures.json` with an error starting `could not be decrypted:`, names each
+  such album's ID in a printed line, or with `--json` in `undecryptableAlbums`,
+  and exits 1 while any remain. A file whose copy in another album decrypts is
+  not recorded: its original is stored from that copy, and the album where it
+  does not decrypt neither links nor lists it. The read commands answer from
+  what decrypted.
 
 - 2026-10-14: `quak backup` no longer asks the server for changes every 3
   seconds while it runs (issue 183). It opens its library with