feat: add capnp

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

crates/sq-capnp-interface/Cargo.toml

@@ -0,0 +1,12 @@
+[package]
+name = "sq-capnp-interface"
+version.workspace = true
+edition.workspace = true
+
+[dependencies]
+capnp = { workspace = true }
+bytes = { workspace = true }
+tokio-util = { workspace = true, features = ["codec"] }
+
+[build-dependencies]
+capnpc = { workspace = true }