Skema Docs CAST Development Notes (#736)

## Summary of Changes
This PR makes a small modification to the development notes that live in
the skema docs website.
It adds a new small section detailing notes on how to use Var and Name
constructs.
More things related to CAST development will be added to this section
when the need arises.

Resolves #733

docs/dev/cast_frontend.md

@@ -0,0 +1,9 @@
+## CAST FrontEnd Generation Notes
+### Using Var vs Name nodes
+Currently in the CAST generation we have a convention on when to use Var and Name nodes.
+The GroMEt generation depends on these being conistent, otherwise there will be errors in the generation.
+In the future this convention might change, or be eliminated altogether, but for now this is the current set of rules.
+
+- If the variable in question is being stored into (i.e. as the result of an assignment), then we use Var. Even if it's a variable that has already been defined.
+- If the variable in question is being read from (i.e. being used in an expression), then we use Name.
+- Whenever we're creating a function call Call() node, the name of the function is specified using the Name node.

mkdocs.yml

@@ -45,6 +45,7 @@ nav:
         - Generating code2fn model coverage reports: "dev/generating_code2fn_model_coverage.md"
         - Using code ingestion frontends: "dev/using_code_ingestion_frontends.md"
         - Using tree-sitter preprocessor: "dev/using_tree_sitter_preprocessor.md"
+        - CAST Front-end generation: "dev/cast_frontend.md"
     - Coverage:
         - Code2fn coverage reports: "coverage/code2fn_coverage/report.html"
         - TA1 Integration Dashboard: "https://integration-dashboard.terarium.ai/TA1"