fix(server): add the lk go.sum entry the workspace was masking

go build inside the Docker image runs outside the workspace, so server/go.sum
needed the hyperboloide/lk entry that GOWORK resolution was supplying locally.
Caught by the image build, not by go build.

shared/go.mod

@@ -4,12 +4,12 @@ go 1.26.4
 
 require (
 	github.com/google/uuid v1.6.0
+	github.com/hyperboloide/lk v0.0.0-20251220053519-b291812e3216
 	go.mongodb.org/mongo-driver/v2 v2.8.0
 	golang.org/x/crypto v0.54.0
 )
 
 require (
-	github.com/hyperboloide/lk v0.0.0-20251220053519-b291812e3216 // indirect
 	github.com/klauspost/compress v1.17.6 // indirect
 	github.com/xdg-go/pbkdf2 v1.0.0 // indirect
 	github.com/xdg-go/scram v1.2.0 // indirect