Add workflow composition normalization

[sezallagwal]

Summary

• Add normalization for workflow composer input
• Convert shorthand fields into the final workflow format
• Normalize event parameter references and template fields
• Flatten nested workflow steps into a single step list
• Return warnings when the composer automatically fixes or rewrites input

Depends on

#8

[dhairyashiil]

Hi Sezal, could we adjust the FOR_EACH / AS alias handling here?

Right now aliases like AS ch are treated globally during normalization. So a later step that is not inside that loop can still write {{ch.name}}, and it gets rewritten as {{steps.ch.name}}. That composes, but at runtime the alias does not exist there and the value becomes empty.

Could we scope the alias only to the step that owns the FOR_EACH, mainly inside that step’s inputMapping? Outside that scope, references like {{ch.name}} should probably fail validation.

This will make workflow behavior easier to reason about and avoid silent empty values later.