feat: implement Phase 1 TCP client

Cargo.toml

@@ -0,0 +1,33 @@
+[package]
+name = "fumi"
+version = "0.1.0"
+edition = "2021"
+description = "Smol Mail client"
+
+[[bin]]
+name = "fumi"
+path = "src/main.rs"
+
+[features]
+# RNS carrier over microReticulum (RNS.md); needs MICRORETICULUM_SOURCE_DIR
+# at build time, provided by the flake.
+rns = ["dep:cc"]
+
+[dependencies]
+snow = "0.9"
+chacha20poly1305 = "0.10"
+ed25519-dalek = { version = "2", features = ["rand_core"] }
+x25519-dalek = { version = "2", features = ["static_secrets"] }
+sha2 = "0.10"
+hmac = "0.12"
+hkdf = "0.12"
+rand_core = { version = "0.6", features = ["getrandom"] }
+rusqlite = { version = "0.32", features = ["bundled"] }
+data-encoding = "2"
+clap = { version = "4", features = ["derive"] }
+log = "0.4"
+env_logger = "0.11"
+anyhow = "1"
+
+[build-dependencies]
+cc = { version = "1", optional = true }