Fixed: Task server is not configured

[Apprentice2907]

Description

This PR fixes the issue where the “TaskServer is not configured” banner remained visible indefinitely on the Home screen.

The banner now:

• Auto-dismisses after a short delay
• Can be manually dismissed by the user
• Does not reappear repeatedly on widget rebuilds

The fix is limited to UI/UX behavior and does not modify TaskServer parsing or backend logic.

Fixes #577

Screenshots

N/A (UI behavior change – auto and manual dismissal)

Checklist

• Tests have been added or updated to cover the changes

  No automated tests were added; behavior was verified manually.

• Documentation has been updated to reflect the changes

  No documentation changes required.

• Code follows the established coding style guidelines
• All tests are passing

[SGI-CAPP-AT2]

Code looks irrelevant to issue
Also checks are failed

[Apprentice2907]

The remaining CI failure is due to existing analyzer lints that are treated as errors via analysis_options.yaml (e.g. library_private_types_in_public_api, curly_braces_in_flow_control_structures, depend_on_referenced_packages).

These issues are unrelated to the “Task server is not configured” fix and pre-exist on this branch.

I’ve fixed all new analyzer errors introduced by this change.

Happy to submit a follow-up PR to address analyzer debt if desired.