Dispatch long file operations and product processing to background threads

[seer-by-sentry]

Fixes IOS-4. The issue was that: Synchronous, recursive CPU-bound Fibonacci calculations and extensive recursive file I/O operations on the main thread during viewDidLoad caused app hanging.

• Moves performLongFileOperation, processProducts, and readCurrentDirectory functions to background threads using DispatchQueue.global(qos: .background).async.
• This prevents blocking the main thread during these operations, improving UI responsiveness.

This fix was generated by Seer in Sentry, triggered by Rohan Agarwal. 👁️ Run ID: 53579

[codecov]

Codecov Report

Attention: Patch coverage is 69.56522% with 7 lines in your changes missing coverage. Please review.

Project coverage is 36.148%. Comparing base (5663891) to head (dc32514).

Files with missing lines	Patch %	Lines
EmpowerPlant/EmpowerPlantViewController.swift	69.565%	6 Missing and 1 partial ⚠️

Additional details and impacted files

@@              Coverage Diff              @@
##            master      #107       +/-   ##
=============================================
- Coverage   37.877%   36.148%   -1.730%     
=============================================
  Files           10        10               
  Lines         1027      1054       +27     
  Branches       323       342       +19     
=============================================
- Hits           389       381        -8     
- Misses         629       663       +34     
- Partials         9        10        +1     

Files with missing lines	Coverage Δ
EmpowerPlant/EmpowerPlantViewController.swift	58.611% <69.565%> (-1.750%)	⬇️

... and 1 file with indirect coverage changes

---

Continue to review full report in Codecov by Sentry.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 5663891...dc32514. Read the comment docs.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.