Better optional values handling

[andrzejressel]

Closes #414

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 98.70690% with 3 lines in your changes missing coverage. Please review.

Project coverage is 80.04%. Comparing base (974a800) to head (cb65711).

✅ All tests successful. No failed tests found.

Files with missing lines	Patch %	Lines
pulumi_wasm_core/src/nodes.rs	71.42%	2 Missing ⚠️
pulumi_wasm_core/src/pulumi/service_impl.rs	0.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #430      +/-   ##
==========================================
+ Coverage   77.95%   80.04%   +2.09%     
==========================================
  Files          25       25              
  Lines        2654     2872     +218     
==========================================
+ Hits         2069     2299     +230     
+ Misses        585      573      -12     

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