feat(envoy-client): fully flesh out tunnel impl

[MasterPtato]

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

[MasterPtato]

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• feat: native SQLite backend via napi-rs with KV channel protocol #4496
• fix: optimize e2e actor path #4551
• feat(pb): actor v1 to v2 migration #4548
• feat(envoy-client): fully flesh out tunnel impl #4547 👈 (View in Graphite)
• feat: basic rivetkit impl #4544
• feat: basic envoy tunnel impl #4534
• chore: envoy client #4521 : 1 other dependent PR (#4531 )
• feat(pb): actors v3 #4463
• feat(ups): implement queue subs #4486
• feat(cache): add in flight deduping #4459
• fix(cache): clean up lib #4457
• fix(config): allow configuring topo dcs via map, fix pg ssl mode config #4456
• fix(api): dont 500 on cross dc response #4449
• chore: update byte units on frontend #4444
• fix: runner alloc idx logic, api auth for actor get #4443
• main

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[railway-app]

🚅 Deployed to the rivet-pr-4547 environment in rivet-frontend

Service	Status	Web	Updated (UTC)
frontend-inspector	❌ Build Failed (View Logs)	Web	Apr 3, 2026 at 1:25 am
website	❌ Build Failed (View Logs)	Web	Apr 3, 2026 at 1:25 am
frontend-cloud	❌ Build Failed (View Logs)	Web	Apr 3, 2026 at 1:25 am
kitchen-sink	❌ Build Failed (View Logs)	Web	Apr 3, 2026 at 1:24 am
mcp-hub	✅ Success (View Logs)	Web	Apr 2, 2026 at 2:48 am
ladle	❌ Build Failed (View Logs)	Web	Apr 2, 2026 at 2:48 am