refactor(l10n): default strings to all targets

Most strings were imported with a platform-specific `targets` (usually
apple-only) just because that's where they happen to be used today. Drop the
restriction so they default to all targets and are available to KMP too; only
the four literal `%@…` format-composition keys stay apple-only.

Also fix the placeholder parser to tolerate C length modifiers (`%lld`), and
give progress_sending_to_count a proper int arg so it emits `%1$d` on both
platforms instead of a literal `%lld`.

apple/VniDrop/Resources/Localizable.xcstrings

@@ -1684,7 +1684,7 @@
         "en": {
           "stringUnit": {
             "state": "translated",
-            "value": "Sending to %lld"
+            "value": "Sending to %1$d"
           }
         }
       }