feat: add capnp

Signed-off-by: kjuulh <contact@kjuulh.io>

crates/sq-sim/Cargo.toml

@@ -7,6 +7,9 @@ edition.workspace = true
 anyhow = { workspace = true }
 tokio = { workspace = true }
 tracing = { workspace = true }
+thiserror = { workspace = true }
 
 [dev-dependencies]
 tokio = { workspace = true, features = ["full", "test-util"] }
+sq-storage = { workspace = true }
+sq-models = { workspace = true }