Removed Navigator from codebase

[anandwana001]

Fixes #2895

@shobhitagarwal1612 PTAL?

[codecov]

Codecov Report

Attention: Patch coverage is 41.66667% with 7 lines in your changes missing coverage. Please review.

Project coverage is 62.58%. Comparing base (85ac644) to head (b1ed231).
Report is 1 commits behind head on master.

Files with missing lines	Patch %	Lines
...ain/java/com/google/android/ground/MainActivity.kt	28.57%	4 Missing and 1 partial ⚠️
...oid/ground/ui/offlineareas/OfflineAreasFragment.kt	50.00%	0 Missing and 2 partials ⚠️

Additional details and impacted files

@@             Coverage Diff              @@
##             master    #2898      +/-   ##
============================================
- Coverage     62.67%   62.58%   -0.09%     
+ Complexity     1209     1203       -6     
============================================
  Files           269      267       -2     
  Lines          6373     6356      -17     
  Branches        879      877       -2     
============================================
- Hits           3994     3978      -16     
+ Misses         1832     1831       -1     
  Partials        547      547              

Files with missing lines	Coverage Δ
...id/ground/ui/offlineareas/OfflineAreasViewModel.kt	100.00% <100.00%> (ø)
...oid/ground/ui/offlineareas/OfflineAreasFragment.kt	66.66% <50.00%> (-3.71%)	⬇️
...ain/java/com/google/android/ground/MainActivity.kt	47.72% <28.57%> (+0.41%)	⬆️