Add typed Python interop contracts

[natashaannn]

Add typed Python interop contracts

Objective

Create shared TypeScript interfaces for JSON emitted by Python pipeline steps.

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Why this matters

JS/Python boundaries currently rely on implicit shape assumptions.

Typed contracts reduce silent integration failures.

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Parallelization metadata

Track

scripts

Depends on

• none

Safe to run in parallel with

• pipeline node issues
• remotion utility issues

Merge risk

• low

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Files in scope

Primary:

• scripts/types/python-interop.ts

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Required implementation

1. Add interfaces for key Python outputs

At minimum include:

• DiarizationSegment
• AlignmentResult
• TranscriberToken

2. Use real current output shapes

Mirror current emitted JSON.

3. Keep additive

No broad script migration yet.

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Constraints

• no runtime validation yet

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Handoff contract

Future script migrations should import these instead of inventing local types.

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Acceptance criteria

Functional

• type file compiles cleanly

Integration checks

• at least one script can import the types

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Verification commands

tsc --noEmit

Expected result:

• zero errors

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Explicitly out of scope

• schema validation
• Python code changes

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Suggested branch

refactor/s6-python-interop

Suggested commit slug

phase-3-step-4-python-interop-types