fix(codegen): use correct deleted{Entity}NodeId field in delete mutation

[yyyyaaa]

Problem

The React Query hooks generator was producing delete mutations with a hardcoded deletedId field, but our backend convention switched to use type-specific field names. I think this is very recent?

deleted{EntityName}NodeId

Before (broken)

deleteUser(input: $input) { deletedId }

After (correct)

deleteUser(input: $input) { deletedUserNodeId }

Solution

• Added getDeletedNodeIdFieldName() helper that infers the correct field name from the TypeRegistry (schema introspection), with fallback to PostGraphile naming convention
• Updated buildDeleteMutationAST() and generateDeleteMutationHook() to use the inferred field name
• Passed TypeRegistry from the codegen orchestrator to mutation generators