feat: add plugin button and navigation slots for enhanced plugin integration across various components

src/app/pages/client/space/Space.tsx

@@ -68,6 +68,7 @@ import { useClosedNavCategoriesAtom } from '../../../state/hooks/closedNavCatego
 import { useStateEvent } from '../../../hooks/useStateEvent';
 import { Membership, StateEvent } from '../../../../types/matrix/room';
 import { stopPropagation } from '../../../utils/keyboard';
+import { PluginNavSlot } from '../../../features/settings/plugins/PluginNavSlot';
 import { getMatrixToRoom } from '../../../plugins/matrix-to';
 import { getViaServers } from '../../../plugins/via-servers';
 import { useSetting } from '../../../state/hooks/settings';
@@ -549,6 +550,7 @@ export function Space() {
                 </NavItemContent>
               </NavLink>
             </NavItem>
+              <PluginNavSlot location="channel-list" />
           </NavCategory>
           <NavCategory
             style={{