fix: Clean up Rust warnings and add Python vital signs detection

Rust changes:
- Fix unused variable warnings in wifi-densepose-nn (densepose.rs, inference.rs, tensor.rs, translator.rs)
- Remove unused imports in wifi-densepose-mat (breathing.rs, pipeline.rs, csi_receiver.rs, debris_model.rs, vital_signs_classifier.rs)
- All tests continue to pass

Python changes:
- Add vital_signs.py module with BreathingDetector and HeartbeatDetector classes
- Mirror Rust wifi-densepose-mat detection functionality
- Update v1 package version to 1.2.0
- Export new vital signs classes from core module

rust-port/wifi-densepose-rs/crates/wifi-densepose-mat/src/detection/breathing.rs

@@ -1,6 +1,6 @@
 //! Breathing pattern detection from CSI signals.
 
-use crate::domain::{BreathingPattern, BreathingType, ConfidenceScore};
+use crate::domain::{BreathingPattern, BreathingType};
 
 /// Configuration for breathing detection
 #[derive(Debug, Clone)]

rust-port/wifi-densepose-rs/crates/wifi-densepose-mat/src/detection/pipeline.rs

@@ -3,7 +3,7 @@
 //! This module provides both traditional signal-processing-based detection
 //! and optional ML-enhanced detection for improved accuracy.
 
-use crate::domain::{ScanZone, VitalSignsReading, ConfidenceScore};
+use crate::domain::{ScanZone, VitalSignsReading};
 use crate::ml::{MlDetectionConfig, MlDetectionPipeline, MlDetectionResult};
 use crate::{DisasterConfig, MatError};
 use super::{

rust-port/wifi-densepose-rs/crates/wifi-densepose-mat/src/integration/csi_receiver.rs

@@ -28,8 +28,6 @@ use chrono::{DateTime, Utc};
 use std::collections::VecDeque;
 use std::io::{BufReader, Read};
 use std::path::Path;
-use std::sync::Arc;
-use tokio::sync::{mpsc, Mutex};
 
 /// Configuration for CSI receivers
 #[derive(Debug, Clone)]

rust-port/wifi-densepose-rs/crates/wifi-densepose-mat/src/ml/debris_model.rs

@@ -16,13 +16,10 @@
 //! - Depth estimation head with uncertainty (mean + variance output)
 
 use super::{DebrisFeatures, DepthEstimate, MlError, MlResult};
-use ndarray::{Array1, Array2, Array4, s};
-use std::collections::HashMap;
+use ndarray::{Array2, Array4};
 use std::path::Path;
-use std::sync::Arc;
-use parking_lot::RwLock;
 use thiserror::Error;
-use tracing::{debug, info, instrument, warn};
+use tracing::{info, instrument, warn};
 
 #[cfg(feature = "onnx")]
 use wifi_densepose_nn::{OnnxBackend, OnnxSession, InferenceOptions, Tensor, TensorShape};

rust-port/wifi-densepose-rs/crates/wifi-densepose-mat/src/ml/mod.rs

@@ -35,7 +35,6 @@ pub use vital_signs_classifier::{
 };
 
 use crate::detection::CsiDataBuffer;
-use crate::domain::{VitalSignsReading, BreathingPattern, HeartbeatSignature};
 use async_trait::async_trait;
 use std::path::Path;
 use thiserror::Error;

rust-port/wifi-densepose-rs/crates/wifi-densepose-mat/src/ml/vital_signs_classifier.rs

@@ -27,12 +27,8 @@ use crate::domain::{
     BreathingPattern, BreathingType, HeartbeatSignature, MovementProfile,
     MovementType, SignalStrength, VitalSignsReading,
 };
-use ndarray::{Array1, Array2, Array4, s};
-use std::collections::HashMap;
 use std::path::Path;
-use std::sync::Arc;
-use parking_lot::RwLock;
-use tracing::{debug, info, instrument, warn};
+use tracing::{info, instrument, warn};
 
 #[cfg(feature = "onnx")]
 use wifi_densepose_nn::{OnnxBackend, OnnxSession, InferenceOptions, Tensor, TensorShape};