Wire e2e smoke harness into CI as a PR gate #113

Problem

The e2e smoke harness (apps/server/scratchpad/e2e-smoke.ts) boots the real server in-process, authenticates, opens a real WebSocket connection, and exercises 10 RPC methods end-to-end. It caught a critical regression (8 missing RPC scope declarations in #73/8834e517) that unit tests missed entirely.

The regression was missed because:

1. Unit tests exercise individual deciders/services in isolation — they don't boot the full server
2. Adding a method to WsRpcGroup without a corresponding entry in RPC_REQUIRED_SCOPE causes a connection-level protocol defect that tears down the entire WebSocket — but no unit test exercises the full handler → RPC framework → WS connection path
3. The merge went through without any gate that booted the real server end-to-end

The harness currently lives in apps/server/scratchpad/ and is not wired into any CI pipeline.

Proposal

Wire apps/server/scratchpad/e2e-smoke.ts into CI as a required gate for PRs. Options:

• Wrap it in a Vitest suite inside apps/server so it runs alongside existing tests
• Add it as a separate CI job that runs after the main test suite
• Run it in the existing CI workflow as a final smoke-check step

Relevant: the existing wsRpcScopes.test.ts regression test already guards the static scope-map, but e2e-smoke guards against runtime contract-implementation drift (e.g. handler signatures not matching Rpc.make contracts after Effect v4 schema changes).