Enhancing ATA.forecasting R Package

Enhancing ATA.forecasting Package in R to Support External Regressors (xreg)
Description:
Hi there,
I'm looking for an R programming expert to help modify the ATA.forecasting package so that it can support external regressors (xreg), similar to how the es() function in the smooth package does.

Objective:
The goal is to include external variables in the ATA() model as regression terms, making the package more flexible and usable in real-world forecasting scenarios with explanatory variables.

Requirements:

Add xreg support to the ATA() function within the ATA.forecasting package.
The model should incorporate external regressors appropriately in the forecasting process.
The code should be clean, well-documented, and ideally structured in a way that can be integrated back into the package format.
A demo or test with example data to verify functionality would be a strong plus.
Ideal Candidate Profile:

Proficient in R programming with strong understanding of time series forecasting
Previous experience with model development or modification within R packages
Familiarity with packages like smooth, forecast, fable, etc.
Able to communicate technical decisions clearly
Delivery Timeline:
Flexible, based on the scope discussed. Can be finalized after an initial evaluation.

If you're interested, please share relevant experience, examples of similar work, or a quick idea on how you would approach this task. Clear and collaborative communication is highly appreciated.