Polish Community launch and picker windows

[8damon]

Summary

Track Community UI polish for the launch, picker, diagnostics, loading, and startup windows.

Scope

• Keep hover states readable by forcing dark text on light hover/pressed buttons.
• Soften harsh borders while preserving usable panel separation.
• Widen launch parameters so controls fit horizontally without clipped rows.
• Add a clear button and close action to process filtering.
• Remove non-functional startup rule-intel blocks from the first-run flow.

Acceptance criteria

• WPF interface builds in Debug.
• The interface process starts without immediate startup failure.
• Added UI text does not expose private server, managed-agent, or private hypervisor features.