Provide option to extract Directional Creep Strain like Creep_strain_XY()

### 📝 Description of the feature

Extracting creep strain directional components are very important for simulation insights in Electronic Reliability analysis.

Right now I don't see any API to get directional creep strain components, though i see an API for accumulated equivalent creep strain
dpf.operators.result.accu_eqv_creep_strain()

I also see an API to get directional PLASTIC strain components
op = dpf.operators.result.plastic_strain_XY()

Similarly provide an option to get directional CREEP Strain components. Equivalent MPADL command is EPCRx

### 💡 Steps for implementing the feature

_No response_

### 🔗 Useful links and references

_No response_

Start by comparing the existing dpf.operators.result.accu_eqv_creep_strain() and plastic_strain_XY() APIs, using EPCRx as the equivalent MPADL reference. Done means the API exposes directional creep strain components for Electronic Reliability analysis and has behavior consistent with the existing directional plastic-strain operator.

Written by the indexing model from the issue text.