security(books): enforce per-file mutation permissions

Require explicit delete or metadata-edit permission before mutating a book file. Keep catalog state intact when physical deletion fails.

Closes #1293

server/test/e2e/authorization-matrix/route-inventory/manifest.json

@@ -1,10 +1,10 @@
 {
-  "totalRoutes": 453,
+  "totalRoutes": 455,
   "byPermission": {
     "(none)": 168,
     "Permission.ManageMetadataConfig": 34,
     "Permission.EmailSend": 30,
-    "Permission.LibraryEditMetadata": 34,
+    "Permission.LibraryEditMetadata": 35,
     "Permission.BookDockAccess": 17,
     "Permission.ManageAppSettings": 39,
     "Permission.ManageLibraries": 17,
@@ -17,7 +17,7 @@
     "Permission.OpdsAccess": 4,
     "Permission.ViewAuditLog": 1,
     "Permission.ViewUserActivity": 6,
-    "Permission.LibraryDeleteBooks": 10,
+    "Permission.LibraryDeleteBooks": 11,
     "Permission.LibraryDownload": 1,
     "Permission.LibraryUpload": 2,
     "Permission.ManageBookDock": 3,