port: upstream PR #1342 - Book Info screen, richer metadata, safer controls

Ports upstream PR #1342 (feat: Add Book Info screen, richer metadata,
and safer file-browser controls) with mod-specific adaptations:

- Parse and cache series, seriesIndex, description from EPUB OPF
- Bump book.bin cache version to 6 for new metadata fields
- Add BookInfoActivity (new screen) accessible via Right button in FileBrowser
- Add ManageBook menu via Left button in FileBrowser (replaces upstream hidden delete)
- Guard all delete/archive actions with ConfirmationActivity (10 call sites)
- Add inputArmed gating to ConfirmationActivity to prevent accidental confirmation
- Safe deserialization: readString now returns bool with MAX_STRING_LENGTH guard
- Add series field to RecentBooksStore with JSON and binary serialization
- Add i18n keys: STR_BOOK_INFO, STR_AUTHOR, STR_SERIES, STR_FILE_SIZE, etc.

Made-with: Cursor

lib/KOReaderSync/KOReaderCredentialStore.cpp

@@ -80,22 +80,29 @@ bool KOReaderCredentialStore::loadFromFile() {
 
   // Read username
   if (file.available()) {
-    serialization::readString(file, username);
+    if (!serialization::readString(file, username)) {
+      file.close();
+      return false;
+    }
   } else {
     username.clear();
   }
 
-  // Read and deobfuscate password
   if (file.available()) {
-    serialization::readString(file, password);
-    obfuscate(password);  // XOR is symmetric, so same function deobfuscates
+    if (!serialization::readString(file, password)) {
+      file.close();
+      return false;
+    }
+    obfuscate(password);
   } else {
     password.clear();
   }
 
-  // Read server URL
   if (file.available()) {
-    serialization::readString(file, serverUrl);
+    if (!serialization::readString(file, serverUrl)) {
+      file.close();
+      return false;
+    }
   } else {
     serverUrl.clear();
   }