refactor(yaml): eliminate shared class state by passing parameters in LoaderState

[timreichen]

This PR removes the tag, anchor, kind and result class properties in LoaderState and passes a State object to methods that change these properties.
It also makes read*() methods return a State to which automatically entangles lots of nested if/else statements.

This reduces the code complexity massively because these properties are changed recursively and sometimes also backtracked which makes the code very hard to follow and methods not
This also opens the door to reduce the code further in future PRs because it makes redundant code and simplifications obvious.

[codecov]

Codecov Report

❌ Patch coverage is 91.59664% with 20 lines in your changes missing coverage. Please review.
✅ Project coverage is 94.28%. Comparing base (c835e4d) to head (e945690).
⚠️ Report is 6 commits behind head on main.

Files with missing lines	Patch %	Lines
yaml/_loader_state.ts	91.59%	18 Missing and 2 partials ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #6902      +/-   ##
==========================================
+ Coverage   94.22%   94.28%   +0.06%     
==========================================
  Files         584      584              
  Lines       43146    43182      +36     
  Branches     6908     6926      +18     
==========================================
+ Hits        40653    40714      +61     
+ Misses       2441     2415      -26     
- Partials       52       53       +1     

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