feat: add repair parts tracking

backend/app/repairs/exceptions.py

@@ -135,3 +135,38 @@ class MacOwnershipConflict(ControlBoardReplacementConflict):
         super().__init__(
             "MAC address has current or historical ownership on another miner"
         )
+
+
+class RepairPartNotFound(RepairError):
+    """Raised when a nested repair-part UUID does not exist for a repair."""
+
+    def __init__(self, repair_part_id: object):
+        self.repair_part_id = repair_part_id
+        super().__init__(f"Repair part not found: {repair_part_id}")
+
+
+class RepairPartComponentNotFound(RepairError):
+    """Raised when a tracked component UUID does not exist."""
+
+    def __init__(self, component_id: object):
+        self.component_id = component_id
+        super().__init__(f"Component not found: {component_id}")
+
+
+class RepairPartValidationError(RepairError):
+    """Raised when repair-part input violates a domain rule."""
+
+
+class RepairPartActorRequired(RepairError):
+    """Raised when a repair-part action lacks an authenticated actor."""
+
+    def __init__(self):
+        super().__init__("An authenticated actor is required for repair-part actions")
+
+
+class RepairPartAlreadyVoided(RepairConflict):
+    """Raised when an immutable repair-part entry was already voided."""
+
+    def __init__(self, repair_part_id: object):
+        self.repair_part_id = repair_part_id
+        super().__init__(f"Repair part is already voided: {repair_part_id}")