fix(rs): clone before move token in downloaderJob

fix(frontend): refine ReaderUI instance checks in MangaReader

- Use explicit nil check for ReaderUI.instance in show method.
- Remove redundant ReaderUI.instance check in initializeFromReaderUI as it uses the passed ui parameter.

Closes #36, #37

fix: reduce search limits and defer error dialog display

fix(backend): improve manga search sorting with unicode normalization

- Add `unicode-normalization` dependency.
- Normalize titles to NFKC and lowercase before sorting in `search_mangas`.
- This ensures consistent and case-insensitive sorting for search results.

fix: Improve manga search robustness and error handling

This change introduces several improvements to the manga search functionality:

- Implements a timeout for each source search to prevent the entire search process from getting stuck on a single unresponsive source.
- Captures and returns errors from individual sources instead of just logging them.
- Displays search errors to the user in the frontend, providing better feedback on why some results might be missing.

fix: Cancel request api (#33)

* fix(lua): Add cancellation support for long-running operations

Implement cancellation tokens for manga operations including search, chapter refresh, detail refresh, and downloads. Add cancel request endpoint and token management system to allow users to cancel in-progress operations from the frontend.

* feat(cancellation): Improve request cancellation handling

This commit refactors the request cancellation logic on both the frontend and backend.

Backend:
- Introduces a  that automatically handles the lifecycle of cancellation tokens, ensuring they are cleaned up properly. This simplifies the code in API route handlers.

Frontend:
- The  now properly signals when it has been cancelled.
- UI flows are updated to check for this cancellation signal and halt further execution, preventing unnecessary processing or error messages when a user cancels an operation (e.g., searching, refreshing chapters).
- This leads to a more responsive and intuitive user experience when dismissing long-running tasks.

* fix(cancellation): Refine cancellation mechanism and frontend cleanup

This commit introduces further refinements to the request cancellation mechanism and includes a minor frontend code cleanup.

Backend:
- Improved the  logic to directly remove the cancellation token from the store, reducing potential race conditions.
- Adjusted the 's drop implementation to use , ensuring immediate removal of cancelled tokens.
- Optimized  by passing a reference to the cancellation token instead of cloning it.

Frontend:
- Removed a redundant  require statement in  as it's now loaded globally within the file.

* ?

chore: add ci

ci: remove setup cachix in build

fix(frontend): Simplify navigation and back button logic

This commit refactors the way the navigation stack () and the back button () are handled across several UI components.

The previous implementation used a table of callbacks in , which was overly complex and prone to errors. This has been simplified to using a placeholder value, and the  functions have been streamlined.

This change improves the stability and predictability of the back button behavior.

Closes #18

fix: Improve source setting field and handling and error reporting

Closes #17