refact: add cargo "python" feature for pyo3

store/Cargo.toml

@@ -12,6 +12,10 @@ name = "trictrac_store"
 # "staticlib" → used by the C++ OpenSpiel game (cxxengine)
 crate-type = ["cdylib", "rlib", "staticlib"]
 
+[features]
+# Enable Python bindings (required for maturin / AI training). Not available on wasm32.
+python = ["pyo3"]
+
 [dependencies]
 anyhow = "1.0"
 base64 = "0.21.7"
@@ -20,7 +24,7 @@ cxx = "1.0"
 log = "0.4.20"
 merge = "0.1.0"
 # generate python lib (with maturin) to be used in AI training
-pyo3 = { version = "0.23", features = ["extension-module", "abi3-py38"] }
+pyo3 = { version = "0.23", features = ["extension-module", "abi3-py38"], optional = true }
 rand = "0.9"
 serde = { version = "1.0", features = ["derive"] }
 transpose = "0.2.2"

store/src/lib.rs

@@ -20,6 +20,7 @@ pub use dice::{Dice, DiceRoller};
 pub mod training_common;
 
 // python interface "trictrac_engine" (for AI training..)
+#[cfg(feature = "python")]
 mod pyengine;
 
 // C++ interface via cxx.rs (for OpenSpiel C++ integration)

store/src/player.rs

@@ -1,3 +1,4 @@
+#[cfg(feature = "python")]
 use pyo3::prelude::*;
 use serde::{Deserialize, Serialize};
 use std::fmt;
@@ -5,7 +6,7 @@ use std::fmt;
 // This just makes it easier to dissern between a player id and any ol' u64
 pub type PlayerId = u64;
 
-#[pyclass(eq, eq_int)]
+#[cfg_attr(feature = "python", pyclass(eq, eq_int))]
 #[derive(Copy, Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
 pub enum Color {
     White,