refactor(ui): merge duplicate status update functions

[MedCy1]

Refactor(ui): Unify status update logic and remove redundant code

What does this PR do?
This PR simplifies how status updates are handled in the UI by consolidating logic into a single method and removing redundant code.

Key Changes:

• Unified Logic: Updated _update_status to update all relevant UI labels (status_label, status_text, and current_task) simultaneously.
• Callback Update: Changed the InstallerProcess callback to use the main _update_status method instead of the specific helper.
• Dead Code Removal: Deleted the _update_status_text method as it is no longer needed (logic is now handled by _update_status).

Why is this change necessary?
Previously, there were two different methods handling status updates (_update_status and _update_status_text), which led to code duplication and potential inconsistencies in the UI (e.g., the "Current Task" label might not match the logs).
This change ensures that every status update is consistently reflected across all UI elements and keeps the codebase cleaner (DRY principle).

How to test:

1. Run the installer (python app.py).
2. Proceed with an installation.
3. Observe that the status text (logs) and the "Current Task" label stay synchronized and update correctly throughout the process.

[MedCy1]

Calling it a night after little 6 PRs! Apologies to the maintainers' notification bells... I promise I'm done spamming for today. 😅 👋