[macOS] Instance hostname resolution

[sharder996]

This PR implements a DNS resolver that allows the system's mDNSResponder to forward .multipass DNS requests to a thread being run by the Multipass daemon.

Requests come through a UDP socket and the requested hostname has its IP address queried by the Multipass daemon.

This is an MVP solution that provides most of the functionality of instance hostname resolution, but lacks a few potentially useful features such as IPv6 support and reverse lookups. If this direction was to be closen, some further development would be done along with proper unit testing.

[codecov]

Codecov Report

❌ Patch coverage is 31.25000% with 11 lines in your changes missing coverage. Please review.
✅ Project coverage is 87.50%. Comparing base (47526d4) to head (6d8492a).
⚠️ Report is 109 commits behind head on main.

Files with missing lines	Patch %	Lines
src/daemon/daemon.cpp	21.43%	11 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #5005      +/-   ##
==========================================
- Coverage   87.77%   87.50%   -0.26%     
==========================================
  Files         273      275       +2     
  Lines       14678    14691      +13     
==========================================
- Hits        12882    12854      -28     
- Misses       1796     1837      +41     

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