feat: Add functionality to search for notes

[JonaFleischmann]

Hi, I added the functionality to search for Notes. Everything I added, I have also translated into German and English.

Closes #407

[codecov]

Codecov Report

Attention: Patch coverage is 4.21053% with 91 lines in your changes are missing coverage. Please review.

Project coverage is 37.01%. Comparing base (8b1088c) to head (50ab56c).

❗ Current head 50ab56c differs from pull request most recent head 84d3ad8. Consider uploading reports for the commit 84d3ad8 to get more accurate results

Files	Patch %	Lines
lib/pages/home/search.dart	1.09%	90 Missing ⚠️
lib/pages/home/home.dart	0.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1137      +/-   ##
==========================================
- Coverage   37.16%   37.01%   -0.16%     
==========================================
  Files         108      109       +1     
  Lines        8500     8592      +92     
==========================================
+ Hits         3159     3180      +21     
- Misses       5341     5412      +71     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

[QubaB]

Thank you for your code, I merged your code to my personal version of Saber.

[zerrium]

Hi, I wonder if this PR can be merged because I want to migrate my personal notes to saber but missing a basic important feature like searching is a really deal breaker for me

[JonaFleischmann]

If there are plans to merge this PR, I can resolve any existing conflicts and re-merge main into this branch.