Remove all stall detection logic, add 100ms current logging

- Removed all STALL_* configuration parameters from config.h
- Simplified motor.h: removed stall-related methods and member variables
- Simplified motor.cpp: deleted checkStall(), resetStallDetection()
- Added frequent current logging (100ms) for data collection
- Removed stall callback system from main.cpp
- Simplified pingpong mode: time-based only, removed stall-return option
- Updated webserver: removed stall warning UI, removed stallReturn checkbox
- Updated status JSON: removed stalled and ppStallReturn fields

This version is for testing with new beefy PSU to collect current data
before designing new stall detection algorithm.

include/config.h

@@ -37,22 +37,8 @@
 #define ADC_VREF 3.3f                 // ADC reference voltage
 #define CURRENT_CALIBRATION 1.0f     // Calibration factor (measured current / reported current)
 
-// Stall Detection Configuration (delta-based)
-// Detects sudden current spikes above the rolling average
-#define STALL_DELTA_THRESHOLD 1.2f    // Current spike above average that indicates stall (amps)
-#define STALL_EMA_ALPHA 0.1f          // EMA smoothing factor (0.1 = slow, 0.5 = fast response)
-#define STALL_EMA_BASELINE 2.0f       // Expected running current baseline for EMA seeding (amps)
-#define STALL_STABILIZE_MS 300        // Ignore stalls for this long after motor starts/changes
-#define STALL_CONFIRM_MS 50           // Current must exceed threshold for this long to confirm stall
-#define DISABLE_STALL_DETECT false    // Set to true to disable stall detection
-
-// Under-current stall detection: motor commanded but drawing no current
-#define STALL_UNDERCURRENT_THRESHOLD 0.5f  // If current below this for too long = stall (amps)
-#define STALL_UNDERCURRENT_MS 1000         // Under-current must persist this long to confirm stall
-
-// Repeated spike stall detection: catches oscillating stall (driver protection cycling)
-#define STALL_CANDIDATE_COUNT 5            // Number of stall candidates in window to confirm stall
-#define STALL_CANDIDATE_WINDOW_MS 2000     // Time window for counting stall candidates
+// Current logging interval for data collection
+#define CURRENT_LOG_INTERVAL_MS 100  // Log current readings every 100ms
 
 // Web Server
 #define HTTP_PORT 80