feat: initial Go/JS/Rust Origin check-in client SDKs

Standalone clients that resolve a machine unique ID (OS machine ID first,
falling back to a generated UUID persisted to disk), detect hostname/IP/
container/orchestrator, and register+re-ping origin.warky.dev's public
service-checkin endpoint on a daily interval. Ported from icy2's internal
origincheckin package but extended to the full check-in contract and made
dependency-light for external reuse.

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

rust/Cargo.toml

@@ -0,0 +1,25 @@
+[package]
+name = "origin-client"
+version = "0.1.0"
+edition = "2021"
+license = "Apache-2.0"
+description = "Origin service check-in client: registers this process with origin.warky.dev and re-pings it on an interval."
+repository = "https://git.warky.dev/wdevs/origin_client"
+
+[dependencies]
+dirs = "5"
+gethostname = "0.5"
+if-addrs = "0.13"
+reqwest = { version = "0.12", default-features = false, features = ["json", "rustls-tls"] }
+serde = { version = "1", features = ["derive"] }
+serde_json = "1"
+tokio = { version = "1", features = ["rt", "time", "macros", "sync"] }
+tokio-util = "0.7"
+uuid = { version = "1", features = ["v4"] }
+
+[target.'cfg(windows)'.dependencies]
+winreg = "0.52"
+
+[dev-dependencies]
+mockito = "1"
+tokio = { version = "1", features = ["rt-multi-thread", "macros", "time"] }