Fix device init: check position before reset to avoid unnecessary homing

Query machine position BEFORE soft reset to determine if homing is needed.
Previously, reset was done first which zeroed position, causing the
comparison to always trigger homing even when machine retained position.

New sequence:
1. Query machine position (before reset)
2. Compare with saved state to decide if homing needed
3. Perform soft reset for clean controller state
4. Home only if position was mismatched

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

modules/connection/connection_manager.py

@@ -197,10 +197,9 @@ def list_serial_ports():
     return available_ports
 
 def device_init(homing=True):
-    # Perform soft reset first to ensure controller is in a known state
-    # This resets position counters to 0 before we query them
-    logger.info("Performing soft reset before device initialization...")
-    perform_soft_reset_sync()
+    # IMPORTANT: Query machine position BEFORE reset to determine if homing is needed
+    # If machine wasn't power cycled, it retains position and we can skip homing
+    # Reset ($Bye) zeroes position counters, so we must check BEFORE reset
 
     try:
         if get_machine_steps():
@@ -214,23 +213,33 @@ def device_init(homing=True):
         state.conn.close()
         return False
 
-    # Reset work coordinate offsets for a clean start
-    # This ensures we're using work coordinates (G54) starting from 0
-    reset_work_coordinates()
-
+    # Check machine position BEFORE reset to decide if homing is needed
     machine_x, machine_y = get_machine_position()
+    needs_homing = False
+
     if machine_x != state.machine_x or machine_y != state.machine_y:
-        logger.info(f'x, y; {machine_x}, {machine_y}')
-        logger.info(f'State x, y; {state.machine_x}, {state.machine_y}')
-        if homing:
-            success = home()
-            if not success:
-                logger.error("Homing failed during device initialization")
+        logger.info(f'Machine position mismatch - machine: ({machine_x}, {machine_y}), saved: ({state.machine_x}, {state.machine_y})')
+        needs_homing = homing
     else:
-        logger.info('Machine position known, skipping home')
+        logger.info('Machine position matches saved state, skipping home')
         logger.info(f'Theta: {state.current_theta}, rho: {state.current_rho}')
-        logger.info(f'x, y; {machine_x}, {machine_y}')
-        logger.info(f'State x, y; {state.machine_x}, {state.machine_y}')
+        logger.info(f'Position: ({machine_x}, {machine_y})')
+
+    # Now perform soft reset to ensure controller is in a clean state
+    # This clears any pending commands and resets position counters to 0
+    logger.info("Performing soft reset for clean controller state...")
+    perform_soft_reset_sync()
+
+    # Reset work coordinate offsets for a clean start
+    # This ensures we're using work coordinates (G54) starting from 0
+    reset_work_coordinates()
+
+    # Home if position was mismatched (machine may have been power cycled)
+    if needs_homing:
+        logger.info("Homing required due to position mismatch...")
+        success = home()
+        if not success:
+            logger.error("Homing failed during device initialization")
 
     time.sleep(2)  # Allow time for the connection to establish
     return True