Validate optical-property vector sizes once, after parsing, not per token

[zhaozhiwen]

getMaterialPropertyFromString appends one value per token in a while(!eof()) loop, and the cross-vector size-validation block sat inside that loop, guarded by if (propertyName == "rayleigh"). On the first rayleigh token only one value has been pushed, so rayleigh.size() == 1; for any real multi-point optical material (photonEnergy size > 1) the very first check fired ERR_GMATERIALOPTICALPROPERTYMISMATCH and aborted loading of valid, consistent data.

Move the validation block out of the token loop so it runs once, after the full property vector has been parsed. propertyName is constant for the call and rayleigh is parsed last, so all other optical vectors are fully populated when the check runs. The check bodies are unchanged (a pure code-motion; the diff is large only because the block de-indents one level).

Validation: the cherenkov optical example (which exercises the same getMaterialPropertyFromString parser for photonEnergy/indexOfRefraction/absorptionLength) still parses its material and runs to completion in the Geant4 11.4.1 dev container. Note: no in-tree example uses rayleigh, so the specific abort path can't be reproduced without authoring new material data.

Fixes #112