Enhance Prisma schema and documentation for dashboard features

- Added new models for DashboardAccessRule and DashboardAuditLog to the Prisma schema, improving access control and logging capabilities.
- Updated GuildSettings model to include timezone support.
- Revised PHASE-TRACKING.md to reflect the completion of Phase 5 and outline upcoming Phase 6 features, including dashboard layout and settings framework.
- Exported new phase 6 features in shared index for better modularity.

apps/webui/postcss.config.mjs

@@ -0,0 +1,5 @@
+const config = {
+  plugins: ["@tailwindcss/postcss"],
+};
+
+export default config;