Fixed: Move canReadFile() method to IO thread.

[MohitMaliFtechiz]

Fixes #4039

• Moved the file readability check to the IO thread to prevent ANR.
• Refactored the code to accommodate this change.
• Refactored the test cases.
• Fixed: The search fragment test failed in both the custom and app modules due to a socket exception during the ZIM file download.
• Improved the search functionality of our application(Since the search was not working properly after this change):
  The article URL was already available in the searchState, but we were redundantly retrieving the article URL from the pageTitle, resulting in an unnecessary extra call to libkiwix. To optimize this, we now directly use the URL provided by libkiwix for the searched item, reducing the additional call.
• Fixed: test search cancellation sometimes fails in CI.

[codecov]

Codecov Report

Attention: Patch coverage is 59.28571% with 57 lines in your changes missing coverage. Please review.

Project coverage is 57.83%. Comparing base (5ceb3ce) to head (9861133).
Report is 17 commits behind head on main.

Files with missing lines	Patch %	Lines
.../kiwix/kiwixmobile/core/main/CoreReaderFragment.kt	40.90%	10 Missing and 3 partials ⚠️
...bile/nav/destination/reader/KiwixReaderFragment.kt	70.58%	4 Missing and 6 partials ⚠️
...java/org/kiwix/kiwixmobile/core/data/Repository.kt	44.44%	10 Missing ⚠️
...r/fileselectView/effects/OpenFileWithNavigation.kt	0.00%	9 Missing ⚠️
.../org/kiwix/kiwixmobile/core/error/ErrorActivity.kt	0.00%	5 Missing ⚠️
...wix/kiwixmobile/core/settings/CorePrefsFragment.kt	0.00%	3 Missing ⚠️
...rg/kiwix/kiwixmobile/core/dao/LibkiwixBookmarks.kt	89.47%	2 Missing ⚠️
.../java/org/kiwix/kiwixmobile/core/dao/NewBookDao.kt	84.61%	1 Missing and 1 partial ⚠️
...kiwixmobile/core/utils/dialog/RateDialogHandler.kt	33.33%	1 Missing and 1 partial ⚠️
...iwix/kiwixmobile/core/extensions/FileExtensions.kt	0.00%	0 Missing and 1 partial ⚠️

Additional details and impacted files

@@             Coverage Diff              @@
##               main    #4040      +/-   ##
============================================
- Coverage     58.17%   57.83%   -0.35%     
+ Complexity     1510     1496      -14     
============================================
  Files           315      315              
  Lines         13020    13071      +51     
  Branches       1657     1659       +2     
============================================
- Hits           7575     7560      -15     
- Misses         4336     4415      +79     
+ Partials       1109     1096      -13     

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