fix: guard against pop and append for constant dynamic arrays

[tserg]

What I did

Fix #3180.

Previously, constancy information was propagated to the folded node as part of the type definition. With #2974, constancy information is now contained in VarInfo. Therefore, we need to additionally propagate VarInfo.

I am not sure if there are any rules as to which nodes can have a type in its metadata, and which nodes can have a varinfo in its metadata. In the approach I have taken, only varinfo is propagated in the metadata. The tradeoff is that this requires us to check for varinfo in get_possible_types_from_node, which I am unsure if it wrongly conflates varinfo with type.

Alternatively, we can also propagate both varinfo and type in the metadata. While this is duplication, it would also mean that we do not need to check for varinfo in get_possible_types_from_node.

How I did it

Create VarInfo object during constant folding, and pass it to the folded node so that it can be retrieved for analysis under the existing validate_modification via visit_Expr in local semantic analysis.

How to verify it

See tests.

Commit message

fix: guard against `pop` and `append` for constant dynamic arrays

Description for the changelog

Guard against pop and append for constant dynamic arrays

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[tserg]

I think this is an outdated comment since pop and append were moved from builtins to codegen.

[codecov-commenter]

Codecov Report

Merging #3189 (75094d3) into master (dcc230c) will increase coverage by 35.24%.
The diff coverage is 88.88%.

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@@             Coverage Diff             @@
##           master    #3189       +/-   ##
===========================================
+ Coverage   53.43%   88.67%   +35.24%     
===========================================
  Files          86       86               
  Lines       10800    10809        +9     
  Branches     2453     2456        +3     
===========================================
+ Hits         5771     9585     +3814     
+ Misses       4493      821     -3672     
+ Partials      536      403      -133     

Impacted Files	Coverage Δ
vyper/ast/folding.py	92.68% <84.61%> (+41.42%)	⬆️
vyper/semantics/analysis/utils.py	91.95% <100.00%> (+45.40%)	⬆️

... and 67 files with indirect coverage changes

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[charles-cooper]

i think generally, we want to use ExprInfo here rather than VarInfo, we might not be dealing with a variable for some reason.

[charles-cooper]

fyi - when i kind of complicated code inlined like this, i'd prefer to see a helper function to do this which is closer to the definition of VarInfo, it's too easy to update the fields of VarInfo and then forget to update all uses of the constructor. in particular, this looks like a good use case for VarInfo.copy_with_type(type_). but as i mentioned in #3189 (review), we probably want to use ExprInfo instead anyway.