feat: add optional session webhook config with retries and signing

[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

[railway-app]

🚅 Deployed to the rivet-pr-4145 environment in rivet-frontend

Service	Status	Web	Updated (UTC)
frontend-inspector	😴 Sleeping (View Logs)	Web	Feb 6, 2026 at 8:10 am
frontend-cloud	😴 Sleeping (View Logs)	Web	Feb 6, 2026 at 8:09 am
website	❌ Build Failed (View Logs)	Web	Feb 6, 2026 at 8:02 am
mcp-hub	✅ Success (View Logs)	Web	Feb 6, 2026 at 8:00 am

[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.
Learn more

• feat: add optional session webhook config with retries and signing #4145 👈 (View in Graphite)
• feat: inspector http api #4144
• main

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[claude]

PR Review - Code Quality Issues

🚨 Critical Issue

This PR appears to contain an accidental commit that should not be merged:

Problem: The PR adds a symlink at the repository root:

node_modules -> /home/nathan/rivet/node_modules

Why this is problematic:

1. Breaks other developers' environments: This symlink points to an absolute path on a specific developer's machine (/home/nathan/), which won't exist for other contributors
2. Should be gitignored: node_modules should already be in .gitignore and should never be committed to the repository
3. Security concern: Committing dependency directories (even as symlinks) can accidentally expose local configuration or credentials
4. Build failures: This will likely cause CI/CD pipeline failures and break local development for others

Mismatch with PR title: The PR title mentions "feat: add optional session webhook config with retries and signing" but the actual changes don't reflect this - only a node_modules symlink was added.

Recommended Actions

1. Remove the symlink: git rm node_modules
2. Verify .gitignore: Ensure node_modules is properly listed in .gitignore
3. Force push to clean history: After removing, force push to update this PR
4. Check for actual changes: The PR description mentions webhook configuration changes, but those files aren't present in the diff. Please verify the correct changes are staged.

Additional Notes

• If this was meant to be a local development convenience, symlinks to node_modules should only exist in your local working directory, never committed to git
• The PR checklist mentions testing and documentation, but there are no code changes to review

Status: ❌ Should not be merged in current state