Function resolve_stack_input_environment_variables 

pub fn resolve_stack_input_environment_variables(
    inputs: &[StackInputDefinition],
    values: &HashMap<String, Value>,
    platform: Platform,
) -> Result<Vec<EnvironmentVariable>>

Environment variables produced by stack inputs that declare env mappings, from the deployment’s input values (or each input’s default).

Only inputs that apply to platform count: an input that lists platforms without it produces nothing. List values become comma-separated strings. Secret inputs produce secret variables unless the mapping sets a type. Two mappings resolving to the same variable name are rejected.