Milestone 1: workspace skeleton, wire protocol, socket round-trip

Three-crate workspace per SPECS.md. varde-proto defines the full JSON
Lines protocol (requests, envelopes, structured errors, events) with
string-typed hashes so the crate carries no iroh dependency. The daemon
binds its unix socket, loads config with flags > env > file > defaults
precedence, and answers status/list; everything else returns a
structured "unimplemented" error. varde-ctl maps subcommands 1:1 onto
requests and round-trips status against a real daemon in the tests.

Dependencies: serde/serde_json (wire format), tokio (async runtime and
unix sockets), tracing/tracing-subscriber (structured logging), toml
(config file), anyhow (binary-edge errors), thiserror (reserved for
library errors), clap (ctl flag parsing, per spec), tempfile (dev-only,
ephemeral test dirs).

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

varde-daemon/Cargo.toml

@@ -0,0 +1,26 @@
+[package]
+name = "varde-daemon"
+description = "varde: content-addressed blob mirror daemon on iroh"
+version.workspace = true
+edition.workspace = true
+license.workspace = true
+repository.workspace = true
+rust-version.workspace = true
+
+[[bin]]
+name = "varde-daemon"
+path = "src/main.rs"
+
+[dependencies]
+varde-proto = { workspace = true }
+anyhow = { workspace = true }
+serde = { workspace = true }
+serde_json = { workspace = true }
+thiserror = { workspace = true }
+tokio = { workspace = true }
+toml = { workspace = true }
+tracing = { workspace = true }
+tracing-subscriber = { workspace = true }
+
+[dev-dependencies]
+tempfile = "3"