fix(ui): Fix version switcher lock when navigating back (bfcache)

[Tugamer89]

What: Added a pageshow event listener in src/main/javadoc/version-switcher.js to detect when the page is restored from the back/forward cache (e.persisted). If it is, the code removes the disabled and aria-busy attributes from the version switcher dropdown, and resets its title attribute.

Why: In Safari and other modern browsers, navigating to a new page via the version switcher dropdown and then clicking the "Back" button caused the page to load from the bfcache. Since the select dropdown was disabled prior to navigation, the page was restored with the dropdown still disabled, permanently locking the user out of selecting a different version.

Before/After: Visually, the disabled state remains the same when initially selecting an option (it greys out to show it is loading). However, upon navigating back, instead of remaining grey and unclickable, the dropdown is now restored to its default interactive state.

Accessibility: Ensures the dropdown becomes accessible again (removes disabled state) and screen reader notifications correctly reset (removes aria-busy flag) when the page is resurrected via the browser's back button.

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PR created automatically by Jules for task 3898747374840787430 started by @Tugamer89

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[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

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