test(server): fuzz ServerCore datagram handling

fuzz/Cargo.toml

@@ -8,11 +8,15 @@ edition = "2021"
 cargo-fuzz = true
 
 [dependencies]
+arbitrary = "1.4.2"
 libfuzzer-sys = "0.4.13"
 
 [dependencies.irtt-proto]
 path = "../crates/irtt-proto"
 
+[dependencies.irtt-server]
+path = "../crates/irtt-server"
+
 # Use independent workspace for fuzzers
 [workspace]
 members = ["."]
@@ -51,3 +55,10 @@ path = "fuzz_targets/decode_varint.rs"
 test = false
 doc = false
 bench = false
+
+[[bin]]
+name = "server_core_datagrams"
+path = "fuzz_targets/server_core_datagrams.rs"
+test = false
+doc = false
+bench = false