fix: migrate some of the codebase to objc2

[grant0417]

Description of changes:
This is progress towards resolving #145

By submitting this pull request, I confirm that you can use, modify, copy, and redistribute this contribution, under the terms of your choice.

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 11.11111% with 232 lines in your changes missing coverage. Please review.

Project coverage is 12.36%. Comparing base (cf16f87) to head (414855f).
Report is 2 commits behind head on main.

Files with missing lines	Patch %	Lines
crates/macos-utils/src/util/notification_center.rs	0.00%	50 Missing ⚠️
crates/macos-utils/src/window_server/mod.rs	0.00%	42 Missing ⚠️
crates/macos-utils/src/image.rs	0.00%	36 Missing ⚠️
crates/fig_input_method/src/macos.rs	0.00%	34 Missing ⚠️
crates/fig_input_method/src/imk.rs	0.00%	18 Missing ⚠️
crates/q_cli/src/util/desktop.rs	0.00%	17 Missing ⚠️
crates/fig_desktop/src/platform/macos.rs	0.00%	7 Missing ⚠️
crates/macos-utils/src/accessibility.rs	0.00%	7 Missing ⚠️
crates/macos-utils/src/applications.rs	65.00%	7 Missing ⚠️
crates/fig_util/src/open.rs	0.00%	4 Missing ⚠️
... and 4 more

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #339      +/-   ##
==========================================
+ Coverage   12.33%   12.36%   +0.02%     
==========================================
  Files        2233     2233              
  Lines      190143   189844     -299     
  Branches   174728   174429     -299     
==========================================
+ Hits        23462    23467       +5     
+ Misses     165514   165209     -305     
- Partials     1167     1168       +1     

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