fix: client perms, @everyone/@channel, docs, unit tests

- usePermissions ORs current user roles + @everyone only (not all server roles)
- cache myRolesByServer; load on active server; refresh after self role edit
- gate/notify @everyone and @channel; plain @username push; special mention UI
- refresh FEATURE_PARITY (DMs exist; drop stale critical gaps)
- README production deploy notes dumpster.service
- unit tests for permission bits and broadcast mention tokens

web/src/components/MemberRoleAssign.tsx

@@ -1,6 +1,6 @@
 import { useEffect, useState } from 'react';
 import { useRoleStore, type Role } from '../stores/role.ts';
-import type { User } from '../stores/auth.ts';
+import { useAuthStore, type User } from '../stores/auth.ts';
 import { usePermissions } from '../lib/usePermissions.ts';
 
 interface MemberRoleAssignProps {
@@ -12,8 +12,10 @@ interface MemberRoleAssignProps {
 export function MemberRoleAssign({ serverId, member }: MemberRoleAssignProps) {
   const roles = useRoleStore((s) => s.roles);
   const fetchRoles = useRoleStore((s) => s.fetchRoles);
+  const fetchMyRoles = useRoleStore((s) => s.fetchMyRoles);
   const setMemberRoles = useRoleStore((s) => s.setMemberRoles);
   const getMemberRoles = useRoleStore((s) => s.getMemberRoles);
+  const currentUserId = useAuthStore((s) => s.user?.id);
 
   const { isOwner, canManageRoles } = usePermissions(serverId);
   const canEdit = isOwner || canManageRoles;
@@ -56,6 +58,9 @@ export function MemberRoleAssign({ serverId, member }: MemberRoleAssignProps) {
     try {
       await setMemberRoles(serverId, member.id, Array.from(selectedIds));
       setMemberRolesState(roles.filter((r) => selectedIds.has(r.id)));
+      if (currentUserId && member.id === currentUserId) {
+        await fetchMyRoles(serverId, currentUserId);
+      }
       setOpen(false);
     } catch {
       // error in store