Remove dead code in expandStringOperand

[AntoineGautier]

The following is dead code and can be remove.

  if (typeof myoperand === "string" && !/^".*"$/.test(operand)) {
    const element =
      typeStore.get(myoperand, basePath) || typeStore.get(myoperand, baseType);
    // Only expand if it's a definition (enum, type, etc.), not an instance parameter
    const isDefinition =
      element && !["component_clause", "import_clause"].includes(element.elementType);
    myoperand = isDefinition ? element.modelicaPath : myoperand;
  }

Tracing through the possible cases for myoperand reaching the if block:

1. Fully qualified type paths (e.g. "Buildings.Fluid.Types.HeatExchangerConfiguration") — typeStore.get finds the Enumeration element, isDefinition = true, but element.modelicaPath === myoperand already, so no change.

2. Import aliases (e.g. "con") — typeStore.get finds the Import element, but elementType === "import_clause" → isDefinition = false, no change.

3. Local parameter references (e.g. "typCtlFanRet") — found as component_clause → isDefinition = false, no change.

4. Enum values (e.g. "...HeatExchangerConfiguration.CounterFlow") — _get splits to name="CounterFlow", parent=Enumeration, isInputGroup("type") = false → while loop never runs → typeStore.get returns undefined → isDefinition = false, no change.

5. MLS predefined types / unparseable paths — typeStore.get returns undefined or bails early, no change.

There is no realistic code path in the Buildings library where element is found, isDefinition is true, AND element.modelicaPath !== myoperand.

And indeed, removing this block has no effect on templates.json.

[AntoineGautier]

Closed with #571.