wip: add type metadata to ast output

[charles-cooper]

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[codecov-commenter]

Codecov Report

Merging #3644 (9d778e0) into master (68da04b) will decrease coverage by 31.96%. The diff coverage is 42.85%.

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@@             Coverage Diff             @@
##           master    #3644       +/-   ##
===========================================
- Coverage   88.66%   56.70%   -31.96%     
===========================================
  Files          86       86               
  Lines       11467    11473        +6     
  Branches     2607     2607               
===========================================
- Hits        10167     6506     -3661     
- Misses        873     4384     +3511     
- Partials      427      583      +156     

Files	Coverage Δ
vyper/compiler/output.py	37.50% <ø> (-54.17%)	:arrow_down:
vyper/ast/nodes.py	71.29% <0.00%> (-22.30%)	:arrow_down:
vyper/semantics/types/base.py	72.26% <50.00%> (-19.35%)	:arrow_down:

... and 66 files with indirect coverage changes

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[charles-cooper]

superseded by https://github.com/vyperlang/vyper/pull/3829