[Python] Store original PyChipError in ChipStackException

This change stores the original PyChipError in ChipStackException so
that details of the original error code can still be retrieved. This
is interesting to use the properties returning processed information
about the original error code. It also preserves the line and code
file which can be helpful.

Author: agners

src/controller/python/chip/exceptions/__init__.py

@@ -15,6 +15,8 @@
 #    limitations under the License.
 #
 
+from __future__ import annotations
+
 __all__ = [
     "ChipStackException",
     "ChipStackError",
@@ -26,15 +28,32 @@
     "UnknownCommand",
 ]
 
+from typing import TYPE_CHECKING
+
+if TYPE_CHECKING:
+    from chip.native import PyChipError
+
 
 class ChipStackException(Exception):
     pass
 
 
 class ChipStackError(ChipStackException):
-    def __init__(self, err, msg=None):
-        self.err = err
-        self.msg = msg if msg else "Chip Stack Error %d" % err
+    def __init__(self, chip_error: PyChipError, msg=None):
+        self.chip_error = chip_error
+        self.msg = msg if msg else "Chip Stack Error %d" % chip_error.code
+
+    @classmethod
+    def from_chip_error(cls, chip_error: PyChipError) -> ChipStackError:
+        return cls(chip_error, str(chip_error))
+
+    @property
+    def chip_error(self) -> PyChipError | None:
+        return self.chip_error
+
+    @property
+    def err(self) -> int:
+        return self.chip_error.code
 
     def __str__(self):
         return self.msg

src/controller/python/chip/native/__init__.py

@@ -116,7 +116,7 @@ def sdk_code(self) -> int:
 
     def to_exception(self) -> typing.Union[None, chip.exceptions.ChipStackError]:
         if not self.is_success:
-            return chip.exceptions.ChipStackError(self.code, str(self))
+            return chip.exceptions.ChipStackError.from_chip_error(self)
 
     def __str__(self):
         buf = ctypes.create_string_buffer(256)