fix(api): subscribe before namespace workflow dispatch

[NathanFlurry]

Description

Please include a summary of the changes and the related issue. Please also include relevant motivation and context.

Type of change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

How Has This Been Tested?

Please describe the tests that you ran to verify your changes.

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes

[NathanFlurry]

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.
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[claude]

Code Review

PR: fix(api): subscribe before namespace workflow dispatch
Status: Draft | +9/-9 lines

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Overview

This PR fixes a classic race condition in the namespace creation API (engine/packages/api-peer/src/namespaces.rs). Previously, the workflow was dispatched before subscriptions were established, meaning if the workflow completed (or failed) very quickly, the events would be emitted before any subscriber was listening — causing the API handler to hang indefinitely waiting for events that already fired.

The fix reorders operations to: subscribe → dispatch → wait, which is the correct pattern for event-driven pub-sub systems.

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Analysis

Correctness: This fix is clearly right.

The original ordering:

1. Dispatch workflow
2. Subscribe to CreateComplete
3. Subscribe to Failed
4. Wait

The fixed ordering:

1. Subscribe to CreateComplete
2. Subscribe to Failed
3. Dispatch workflow
4. Wait

The subscribe-before-publish pattern is fundamental: the listener must be in place before triggering the event source. This is especially important because namespace creation could complete near-synchronously in local/test environments with minimal I/O.

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Observations

• Minimal and focused — no unrelated changes, exactly the right scope.
• No timeout on tokio::select! — if neither CreateComplete nor Failed ever fires (e.g., the workflow panics without signaling), the API handler will wait indefinitely. This is pre-existing behavior not introduced here, but worth noting as a follow-up.
• Subscription cleanup on dispatch failure — if dispatch() fails, create_sub and fail_sub are dropped without use. This is safe as long as the subscription type handles deregistration on drop, which appears to be the case.
• Pattern audit — any other workflow dispatch + subscription patterns in the API layer should be audited for the same subscribe-after-dispatch bug.

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Suggestions

1. Follow-up: add a deadline/timeout to the tokio::select! to prevent indefinite hangs if the workflow silently fails to emit a completion signal.
2. Follow-up: audit other callsites with the dispatch-then-subscribe pattern across the engine API layer to ensure this isn't repeated.

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Summary

This is a correct and necessary bug fix. The change is small, targeted, and applies the right subscribe-before-dispatch ordering. Good to merge once out of draft.