refactor(cfc): Serializer API

[volsa]

[codecov]

Codecov Report

Attention: 59 lines in your changes are missing coverage. Please review.

Comparison is base (ec4b34c) 95.75% compared to head (1d5df7f) 95.68%.
Report is 2 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #967      +/-   ##
==========================================
- Coverage   95.75%   95.68%   -0.07%     
==========================================
  Files         153      153              
  Lines       42413    42301     -112     
==========================================
- Hits        40611    40475     -136     
- Misses       1802     1826      +24     

Files	Coverage Δ
compiler/plc_driver/src/runner.rs	100.00% <100.00%> (ø)
compiler/plc_xml/src/lib.rs	100.00% <ø> (ø)
compiler/plc_xml/src/model/block.rs	97.43% <100.00%> (+2.19%)	⬆️
compiler/plc_xml/src/model/control.rs	94.44% <100.00%> (+2.33%)	⬆️
compiler/plc_xml/src/model/fbd.rs	99.09% <100.00%> (-0.05%)	⬇️
compiler/plc_xml/src/model/interface.rs	90.00% <100.00%> (-5.00%)	⬇️
compiler/plc_xml/src/xml_parser/control.rs	98.97% <100.00%> (-0.63%)	⬇️
compiler/plc_xml/src/xml_parser/pou.rs	85.71% <100.00%> (ø)
compiler/plc_xml/src/model/connector.rs	87.50% <91.66%> (+1.29%)	⬆️
compiler/plc_xml/src/model/variables.rs	80.55% <98.24%> (+2.62%)	⬆️
... and 11 more

... and 9 files with indirect coverage changes

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

[mhasel]

Nice work! Some very minor comments.
Also, the demo.st.out file seems to have snuck into your commits :)