chore: drop dead irpc/irpc-derive workspace deps

irpc 0.16 was declared in the workspace Cargo.toml and consumed by
alknet-call, but no .rs file in the workspace imports it. alknet-call's
wire protocol (src/protocol/wire.rs) is hand-rolled length-prefixed JSON.
The dep was dead weight.

Re-add as 0.17 when alknet-blobs lands (it depends on iroh-blobs 0.103
which pulls irpc 0.17 transitively).

Cargo.toml

@@ -15,6 +15,4 @@ edition = "2021"
 license = "MIT OR Apache-2.0"
 repository = "https://git.alk.dev/alkdev/alknet"
 
-[workspace.dependencies]
-irpc = "0.16"
-irpc-derive = "0.16"
+[workspace.dependencies]

crates/alknet-call/Cargo.toml

@@ -15,7 +15,6 @@ quinn = ["dep:quinn", "dep:rustls", "dep:rustls-native-certs", "dep:rustls-pemfi
 
 [dependencies]
 alknet-core = { path = "../alknet-core" }
-irpc = { workspace = true }
 tokio = { version = "1", features = ["full"] }
 serde = { version = "1", features = ["derive"] }
 serde_json = "1"