Scaffold workspace, shared types and requirements spec

Cargo workspace with core/ble/fit/probe crates. crates/core/src/types.rs
is the fixed contract between the BLE layer, ride engine and UI.

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

Cargo.toml

@@ -0,0 +1,32 @@
+[workspace]
+resolver = "2"
+members = ["crates/core", "crates/ble", "crates/fit", "crates/probe"]
+
+[workspace.package]
+version = "0.1.0"
+edition = "2021"
+license = "MIT"
+repository = "https://github.com/dtourolle/BikeControl"
+
+[workspace.dependencies]
+bikecontrol-core = { path = "crates/core" }
+bikecontrol-ble = { path = "crates/ble" }
+bikecontrol-fit = { path = "crates/fit" }
+
+anyhow = "1"
+thiserror = "2"
+serde = { version = "1", features = ["derive"] }
+serde_json = "1"
+serde_yaml_ng = "0.10"
+tokio = { version = "1", features = ["rt-multi-thread", "macros", "sync", "time"] }
+tracing = "0.1"
+tracing-subscriber = { version = "0.3", features = ["env-filter"] }
+btleplug = "0.11"
+futures = "0.3"
+uuid = "1"
+roxmltree = "0.20"
+chrono = "0.4"
+
+[profile.release]
+lto = true
+opt-level = 3