Fix some more parsing issues

Example of issues we had is that parsing floating point numbers would parse the dot as an attribute syntax and trying to retrieve both sides of the attributes to the get_value resolve. E.g `3.14` would be interpreted as getting the `14` property of the object `3`, which ofcourse throws an error.

CURA-11347

plugins/CuraEngineBackend/StartSliceJob.py

@@ -6,7 +6,7 @@ import numpy
 from string import Formatter
 from enum import IntEnum
 import time
-from typing import Any, cast, Dict, List, Optional, Set
+from typing import Any, cast, Dict, List, Optional, Set, Tuple
 import re
 import pyArcus as Arcus  # For typing.
 from PyQt6.QtCore import QCoreApplication
@@ -68,6 +68,14 @@ class GcodeStartEndFormatter(Formatter):
         self._default_extruder_nr: int = default_extruder_nr
         self._additional_per_extruder_settings: Optional[Dict[str, Dict[str, any]]] = additional_per_extruder_settings
 
+    def get_field(self, field_name, args: [str], kwargs: dict) -> Tuple[str, str]:
+        # get_field method parses all fields in the format-string and parses them individually to the get_value method.
+        # e.g. for a string "Hello {foo.bar}" would the complete field "foo.bar" would be passed to get_field, and then
+        # the individual parts "foo" and "bar" would be passed to get_value. This poses a problem for us, because  want
+        # to parse the entire field as a single expression. To solve this, we override the get_field method and return
+        # the entire field as the expression.
+        return self.get_value(field_name, args, kwargs), field_name
+
     def get_value(self, expression: str, args: [str], kwargs: dict) -> str:
 
         # The following variables are not settings, but only become available after slicing.