fix(event-bus): add diagnostic logging for auth flow in event delivery

[tlgimenes]

Summary

• Adds 11 targeted [EventBus:Debug] diagnostic logs across the event bus → binding auth chain to diagnose "Streamable HTTP error" failures during async event delivery
• Logs trace org context, JWT permissions, membership lookups, and downstream token state at each hop — no full secrets are exposed (tokens truncated to 8-20 chars)
• Covers 6 files: notify.ts, headers.ts, outbound/index.ts, runtime/index.ts, runtime/bindings.ts, context-factory.ts

What to look for in logs

• orgId: "NONE" anywhere → org context is lost in the chain
• permissionKeys missing the BigQuery connection ID → JWT permissions don't grant access
• downstream token expired with no refresh → OAuth token is dead
• JWT membership SKIPPED → second-hop auth has no role, which may block access

Test plan

• Deploy and trigger the event bus flow (publish event → subscriber handles → subscriber calls BigQuery binding)
• Filter logs with grep "EventBus:Debug" and verify the expected log sequence appears
• Confirm the logs reveal which of the three suspects (orgId, permissions, or OAuth token) causes the failure
• Remove diagnostic logs after root cause is identified

🤖 Generated with Claude Code

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Summary by cubic

Adds focused [EventBus:Debug] logs to the event-bus → bindings auth chain to diagnose "Streamable HTTP error" during async event delivery. Traces org context, permission keys, membership results, token issuance/refresh state, and outbound header keys (tokens truncated; no secrets).

^{Written for commit 0f1645a. Summary will update on new commits.}

[github-actions]

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[github-actions]

Release Options

Should a new version be published when this PR is merged?

React with an emoji to vote on the release type:

Reaction	Type	Next Version
👍	Prerelease	2.123.1-alpha.1
🎉	Patch	2.123.1
❤️	Minor	2.124.0
🚀	Major	3.0.0

Current version: 2.123.0

Deployment

• Deploy to production (triggers ArgoCD sync after Docker image is published)

[cubic-dev-ai]

No issues found across 6 files