sausage-plugin part 2: import! with typed clients (sausage_interface::client_rs), TCP endpoints with rpc.endpoint, examples

Part 1 fixes: complete stdout writes, buffered stdin, Rust type names
in schemas, enum variant docs, -32603 for serde errors in handlers,
crate docs and modules. End-to-end check of a generated consumer through
a fake core.

Cargo.lock

@@ -193,6 +193,18 @@ version = "1.12.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "fc652a48c352aef3ea3aed32080501cf3ef6ed5da78602a020c991775b0aff04"
 
+[[package]]
+name = "cap-fs-ext"
+version = "4.0.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "56ff379b70af8e08307a8f65e7040c7301cb4a572538ade16b4984f0da77847f"
+dependencies = [
+ "cap-primitives",
+ "cap-std",
+ "io-lifetimes 3.0.1",
+ "windows-sys 0.61.2",
+]
+
 [[package]]
 name = "cap-primitives"
 version = "4.0.3"
@@ -1884,6 +1896,7 @@ version = "0.1.0"
 dependencies = [
  "async-trait",
  "bytes",
+ "cap-fs-ext",
  "cap-std",
  "proptest",
  "rusqlite",