conformance: flux spec uses wrong endpoint path /flux/stream instead of /api/flux

[lukeocodes]

Problem

The flux conformance spec (interfaces/flux/conformance/stream.spec.js) hardcodes const ENDPOINT = "/flux/stream" but the server exposes the WebSocket at /api/flux.

All other conformance specs follow the pattern:

• process.env.LIVE_TRANSCRIPTION_ENDPOINT || "/api/live-transcription"
• process.env.LIVE_TEXT_TO_SPEECH_ENDPOINT || "/api/live-text-to-speech"
• process.env.VOICE_AGENT_ENDPOINT || "/api/voice-agent"

The flux spec is the only one that:

1. Uses a different path pattern (/flux/stream vs /api/flux)
2. Has no env var override

Failures

All 8 conformance spec tests fail with "socket hang up" (ECONNRESET) because the server's upgrade handler only accepts /api/flux and destroys the socket for any other path.

The API tests (tests/flux/api/stream.test.js) pass because they use the correct endpoint /api/flux.

Fix

Update interfaces/flux/conformance/stream.spec.js to use:

const ENDPOINT = process.env.FLUX_ENDPOINT || "/api/flux";

This is a contracts submodule fix that affects all flux starters.

[lukeocodes]

Deeper investigation

After fixing the endpoint path from /flux/stream to /api/flux, the test results improved from 0/8 to 3/8 passing:

Now passing (3):

• ✅ should connect to WebSocket endpoint with valid stream URL and model
• ✅ should receive Connected event after connection
• ✅ should handle connection close gracefully

Still failing (5):

• ❌ should receive TurnInfo events during streaming — Test expects server to fetch audio from stream_url query param. Server is a WebSocket proxy that expects client to send audio.
• ❌ should return error for missing stream_url parameter — Server doesn't validate/use stream_url at all
• ❌ should return error for missing model parameter — Server hardcodes model=flux-general-en, doesn't validate
• ❌ should return error for invalid stream_url format — No server-side URL validation
• ❌ should return error for unreachable stream_url — No server-side URL fetching

Root cause

The conformance spec was written for a stream-URL ingestion architecture where the server fetches audio from a URL and processes it. But the actual node-flux implementation is a WebSocket proxy architecture where the client sends audio directly.

Two issues in the conformance spec:

1. Endpoint path: /flux/stream instead of process.env.FLUX_ENDPOINT || "/api/flux" (inconsistent with all other conformance specs)
2. Architecture mismatch: stream_url and error validation tests don't apply to the proxy architecture

Recommendation

The conformance spec needs a rewrite to match the proxy-based architecture:

• Remove stream_url related tests (proxy doesn't use it)
• TurnInfo test should send audio data via WebSocket instead of expecting server-side URL fetch
• Error tests should validate actual proxy error scenarios
• Endpoint should follow the standard pattern: process.env.FLUX_ENDPOINT || "/api/flux"

Note: The API tests (tests/flux/api/stream.test.js) all pass — they correctly test the proxy architecture.

Reverting the endpoint fix for now since partial conformance is worse than tracking the full issue.