🌐 Sync Translations + Update README Progress Table (#3531)

### Description of Changes

This Pull Request was automatically generated to synchronize updates to
translation files and documentation. Below are the details of the
changes made:

#### **1. Synchronization of Translation Files**
- Updated translation files (`messages_*.properties`) to reflect changes
in the reference file `messages_en_GB.properties`.
- Ensured consistency and synchronization across all supported language
files.
- Highlighted any missing or incomplete translations.

#### **2. Update README.md**
- Generated the translation progress table in `README.md`.
- Added a summary of the current translation status for all supported
languages.
- Included up-to-date statistics on translation coverage.

#### **Why these changes are necessary**
- Keeps translation files aligned with the latest reference updates.
- Ensures the documentation reflects the current translation progress.

---

Auto-generated by [create-pull-request][1].

[1]: https://github.com/peter-evans/create-pull-request

Co-authored-by: stirlingbot[bot] <195170888+stirlingbot[bot]@users.noreply.github.com>

README.md

@@ -148,7 +148,7 @@ Stirling-PDF currently supports 40 languages!
 | Simplified Chinese (简体中文) (zh_CN)         | ![93%](https://geps.dev/progress/93)   |
 | Slovakian (Slovensky) (sk_SK)                | ![69%](https://geps.dev/progress/69)   |
 | Slovenian (Slovenščina) (sl_SI)              | ![94%](https://geps.dev/progress/94)   |
-| Spanish (Español) (es_ES)                    | ![98%](https://geps.dev/progress/98)   |
+| Spanish (Español) (es_ES)                    | ![99%](https://geps.dev/progress/99)   |
 | Swedish (Svenska) (sv_SE)                    | ![87%](https://geps.dev/progress/87)   |
 | Thai (ไทย) (th_TH)                           | ![80%](https://geps.dev/progress/80)   |
 | Tibetan (བོད་ཡིག་) (zh_BO)                     | ![88%](https://geps.dev/progress/88) |