PIR: Add state engine models for email flexibility

[landomen]

Task/Issue URL: https://app.asana.com/1/137249556945/project/72649045549333/task/1213886961787938?focus=true

Description

Adds state engine models for email flexibility.

Steps to test this PR

Will be testable on upstream PRs once whole feature is finished.

UI changes

No UI changes

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Note

Low Risk
Adds new state/side-effect models and a stub handler for email-data polling; behavior is effectively unchanged until the TODO is implemented, with only minimal wiring added to the runner.

Overview
Extends the PIR actions state engine to support email confirmation/data extraction flows by adding emailExtractedData to engine State plus new events (EmailDataReceived, RetryAwaitEmailData) and a new side effect (SideEffect.AwaitEmailData) carrying polling/extraction parameters.

Wires the runner to recognize AwaitEmailData and adds a placeholder handleAwaitEmailData (TODO) for future implementation, without changing current runtime behavior beyond handling the new side-effect type.

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[landomen]

Warning

This pull request is not mergeable via GitHub because a downstack PR is open. Once all requirements are satisfied, merge this PR as a stack on Graphite.
Learn more

• PIR: Add handling of GenerateEmail action #8294
• PIR: Add broker step action handler logic #8282
• PIR: Add state engine models for email flexibility #8233 👈 (View in Graphite)
• PIR: Add new email flexibility action models #8232
• develop

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