Fix listoferrors

[beniroquai]

This pull request focuses on improving user experience and consistency across the website's measurement and informational pages. The main changes include the addition of a firmware update notice, enhancements to the WebSerial navigation visibility logic, significant UI/UX improvements to the WebSerial measurement page, and updates to language localization for new features.

User Interface and UX Improvements:

• The messung_webserial.html page now features a redesigned control panel, including a serial connection status indicator, sensor settings panel (gain and integration time), and updated button styles to better match messung.html. This enhances usability and consistency for users performing measurements via WebSerial.
• The custom CSS for messung_webserial.html was simplified and aligned with messung.html to ensure a more consistent look and feel across measurement pages.

Feature Additions:

• A prominent firmware flash notice has been added to index.html, encouraging users to update their device firmware directly from the browser.

WebSerial Navigation Logic:

• The logic for displaying the WebSerial navigation item and related UI elements has been improved across multiple pages (index.html, infos.html, justage.html, messung.html, ratio.html). The WebSerial navigation is now only hidden if the browser does not support the WebSerial API or if the backend explicitly disables it, ensuring better user guidance on hosted sites. [1] [2] [3] [4] [5]

Localization and Language Support:

• New language keys and translations were added for the firmware flash notice and the new sensor settings panel, supporting both German and English users. [1] [2] [3] [4]

Navigation Updates:

• The WebSerial measurement page (messung_webserial.html) is now accessible via the navigation bar on the B-Field Monitor page (ratio.html).