Adds a Reports dashboard view (`ReportsView`) to the reports plugin with a full supporting stack of components (`ReportComparisonDrawer`, `ReportDetailPanel`, `ReportFiltersBar`, `ReportListItem`, `ReportEmptyState`), hooks (`useReports`, `useReportPreview`, `useReportSectionDiff`, `useViewportMode`
Fusion-Task-Id: FN-3786
The merge introduces a new `fusion-plugin-reports` plugin scaffold with settings schema, manifest, entry point, and tests, alongside a mobile session switcher in the chat header. It also adds a mailbox notifications system with ntfy/webhook providers, cleans up roadmap types from core, and includes
Fusion-Task-Id: FN-3778
