fix(python): constructable GaussianHmmParamsPy + dict-like backtest metrics (nhkk)

quantwave-py/python/quantwave/backtest_types.py

@@ -28,10 +28,18 @@ def as_dict(self) -> dict[str, float]:
 
     def keys(self):
         return self.as_dict().keys()
-        
+
     def __getitem__(self, key: str):
         return getattr(self, key)
 
+    def __contains__(self, key: object) -> bool:
+        # Without this, ``"x" in metrics`` falls back to integer-index iteration
+        # via __getitem__ (getattr(self, 0)) and raises TypeError.
+        return isinstance(key, str) and key in self.as_dict()
+
+    def __iter__(self):
+        return iter(self.keys())
+
 @dataclass(frozen=True)
 class BacktestStats:
     """Core summary statistics from a backtest run."""
@@ -50,6 +58,12 @@ def as_dict(self) -> dict[str, float]:
 
     def keys(self):
         return self.as_dict().keys()
-        
+
     def __getitem__(self, key: str):
         return getattr(self, key)
+
+    def __contains__(self, key: object) -> bool:
+        return isinstance(key, str) and key in self.as_dict()
+
+    def __iter__(self):
+        return iter(self.keys())

quantwave-py/src/indicators.rs

@@ -1883,6 +1883,30 @@ pub struct GaussianHmmParamsPy {
     /// Per-state λ (empty → 1.0 per state, Gaussian mode).
     pub lambdas: Vec<f64>,
 }
+#[pymethods]
+impl GaussianHmmParamsPy {
+    // Constructable from Python (input params, not a read-only result record):
+    // `qw.GaussianHmmParamsPy(n_states, delta, gamma_flat, means, stds, lambdas=[])`.
+    #[new]
+    #[pyo3(signature = (n_states, delta, gamma_flat, means, stds, lambdas = Vec::new()))]
+    pub fn new(
+        n_states: u32,
+        delta: Vec<f64>,
+        gamma_flat: Vec<f64>,
+        means: Vec<f64>,
+        stds: Vec<f64>,
+        lambdas: Vec<f64>,
+    ) -> Self {
+        Self {
+            n_states,
+            delta,
+            gamma_flat,
+            means,
+            stds,
+            lambdas,
+        }
+    }
+}
 
 #[pyclass(get_all)]
 #[derive(Clone)]