Stop attempting to refresh Spring tokens in desktop (#5610)

# Description of Changes

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## Checklist

### General

- [ ] I have read the [Contribution
Guidelines](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/CONTRIBUTING.md)
- [ ] I have read the [Stirling-PDF Developer
Guide](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/devGuide/DeveloperGuide.md)
(if applicable)
- [ ] I have read the [How to add new languages to
Stirling-PDF](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/devGuide/HowToAddNewLanguage.md)
(if applicable)
- [ ] I have performed a self-review of my own code
- [ ] My changes generate no new warnings

### Documentation

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repo](https://github.com/Stirling-Tools/Stirling-Tools.github.io/blob/main/docs/)
(if functionality has heavily changed)
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Tags](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/devGuide/HowToAddNewLanguage.md#add-new-translation-tags)
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[`scripts/counter_translation.py`](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/docs/counter_translation.md)

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---------

Co-authored-by: James Brunton <[email protected]>

frontend/src-tauri/src/lib.rs

@@ -9,17 +9,20 @@ use commands::{
     cleanup_backend,
     clear_auth_token,
     clear_opened_files,
+    clear_refresh_token,
     clear_user_info,
     is_default_pdf_handler,
     get_auth_token,
     get_backend_port,
     get_connection_config,
     get_opened_files,
+    get_refresh_token,
     get_user_info,
     is_first_launch,
     login,
     reset_setup_completion,
     save_auth_token,
+    save_refresh_token,
     save_user_info,
     set_connection_mode,
     set_as_default_pdf_handler,
@@ -143,6 +146,9 @@ pub fn run() {
       save_auth_token,
       get_auth_token,
       clear_auth_token,
+      save_refresh_token,
+      get_refresh_token,
+      clear_refresh_token,
       save_user_info,
       get_user_info,
       clear_user_info,