feat(i18n): Further enhance localization translations

[x-Ai]

Pre-flight Checklist

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• [x] I have read the Contributing Guidelines for this project.
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Description of Change

1. Following the recent code push in #2235, several text strings that had not been internationalized were discovered during routine use; consequently, these missing texts have now been localized.
2. The en-US.json, zh-HANS.json, and zh.json files have now been comprehensively populated to address the full spectrum of localization keys. It is requested that these three files, contained within this push, be deployed to Crowdin to supersede the current versions. This will establish them as the authoritative baseline translations for English, Simplified Chinese, and Chinese. Such a measure is critical to preclude the automated bot from subsequently retrieving incomplete translations, thereby ensuring the integrity of our localization efforts and preventing a fragmented experience in future releases of Ferdium.

Motivation and Context

This change is aimed at providing a complete and unified user interface experience by ensuring that all textual elements are properly internationalized. By consolidating strings into the i18n system with English as the source language, it facilitates easier translation workflows and improves overall application consistency, addressing issues stemming from partial localization and hardcoded text.

Checklist

• [x] My pull request is properly named
• [x] The changes respect the code style of the project (pnpm prepare-code)
• [x] pnpm test passes
• [x] I tested/previewed my changes locally

Release Notes

Improved and completed application translations by fully localizing all Simplified Chinese text and internationalizing hardcoded strings.