Add deterministic hash utility for artifacts

[natashaannn]

Add deterministic hash utility for artifacts

Objective

Introduce a shared deterministic hashing utility for all pipeline artifacts.

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Why this matters

Pipeline correctness depends on stable artifact identity.

Without a shared hashing mechanism, cache + validation are unreliable.

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Parallelization metadata

Track

scripts

Depends on

• Content-addressed artifact store #11

Safe to run in parallel with

• pipeline nodes
• remotion cleanup

Merge risk

• low

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Files in scope

Primary:

• scripts/config/hash.ts

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Required implementation

1. Deterministic hashing function

Must:

• accept JSON or buffer
• produce stable SHA-256

2. Normalize JSON before hashing

Sort keys recursively.

3. Export helper

hashArtifact(content): string

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Constraints

• no filesystem operations

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Acceptance criteria

Functional

• identical inputs produce identical hashes

Unit tests

• JSON ordering test
• binary buffer test

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Verification commands

Run hash on same object twice.

Expected result:

• identical output

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Explicitly out of scope

• pipeline integration changes

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Suggested branch

refactor/s7-hash-utils

Suggested commit slug

phase-3-step-6-hash-utils