v0.9.1

v0.9.1

• Bump package/plugin release version to 0.9.1.
• Align the HTTP server header with the project version: MnemosyneDashboard/0.9.1.
• Refresh the GitHub screenshot gallery after the dashboard IA/search/review/lifecycle polish pass.
• Polish release UX: selected-item Review triage, sidebar command search, clearer Search results, empty/loading/error states, Facts wording, and shorter History copy.