Initial setup for migrating from SharedPreferences to DataStore.

[MohitMaliFtechiz]

Parent Issue #2688

• Created the KiwixDataStore and SharedPreferenceToDatastoreMigrator classes to handle the migration of existing SharedPreferences data to DataStore.
• Migrated the currently opened ZIM file and the currently opened tab to DataStore.
• Migrated the TextZoom value to DataStore (the zoom level configured by the user for reading ZIM files).
• Added DataStore dependency in our project.

[codecov]

Codecov Report

❌ Patch coverage is 77.46479% with 16 lines in your changes missing coverage. Please review.
✅ Project coverage is 58.93%. Comparing base (0b14cf6) to head (e039c30).
⚠️ Report is 2 commits behind head on main.

Files with missing lines	Patch %	Lines
...kiwixmobile/core/main/reader/CoreReaderFragment.kt	33.33%	0 Missing and 6 partials ⚠️
...kiwixmobile/core/utils/datastore/KiwixDataStore.kt	77.27%	2 Missing and 3 partials ⚠️
...wix/kiwixmobile/core/settings/SettingsPresenter.kt	42.85%	4 Missing ⚠️
...bile/nav/destination/reader/KiwixReaderFragment.kt	66.66%	0 Missing and 1 partial ⚠️

Additional details and impacted files

@@             Coverage Diff              @@
##               main    #4514      +/-   ##
============================================
- Coverage     58.96%   58.93%   -0.03%     
- Complexity     1520     1531      +11     
============================================
  Files           324      327       +3     
  Lines         17500    17535      +35     
  Branches       2179     2180       +1     
============================================
+ Hits          10318    10334      +16     
- Misses         5757     5768      +11     
- Partials       1425     1433       +8     

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