fix: e2e suite fails to build (stale server.New call) (#81)

Fixes #80

## Why
`make e2e` did not compile against master: `e2e/e2e_test.go` called `server.New(cfg)` but the signature is `New(cfg, version string)`. This blocked all end-to-end validation.

## Changes
- Pass a static `"e2e-test"` version to `server.New` in the e2e bootstrap.

## Validation
- `make e2e` builds and passes (testcontainers: postgres/redis/minio).

Reviewed-on: #81
Co-authored-by: Ben Vincent <ben@unkin.net>
Co-committed-by: Ben Vincent <ben@unkin.net>

e2e/e2e_test.go

@@ -95,7 +95,7 @@ func TestMain(m *testing.M) {
 	}
 	cfg.ListenAddr = "127.0.0.1:0"
 
-	srv, err := server.New(cfg)
+	srv, err := server.New(cfg, "e2e-test")
 	if err != nil {
 		log.Fatalf("server: %v", err)
 	}