feat: Response mobile layout support v1

toju-app/src/app/domains/server-directory/feature/server-search/server-search.component.ts

@@ -18,6 +18,7 @@ import {
 } from 'rxjs';
 import { NgIcon, provideIcons } from '@ng-icons/core';
 import {
+  lucideArrowLeft,
   lucideExternalLink,
   lucideFileText,
   lucideSearch,
@@ -34,14 +35,15 @@ import {
   selectSearchResults,
   selectIsSearching,
   selectRoomsError,
-  selectSavedRooms
+  selectSavedRooms,
+  selectCurrentRoom
 } from '../../../../store/rooms/rooms.selectors';
 import {
   Room,
   User,
   type PluginRequirementSummary
 } from '../../../../shared-kernel';
-import { ExternalLinkService } from '../../../../core/platform';
+import { ExternalLinkService, ViewportService } from '../../../../core/platform';
 import { SettingsModalService } from '../../../../core/services/settings-modal.service';
 import { DatabaseService } from '../../../../infrastructure/persistence';
 import { type ServerInfo } from '../../domain/models/server-directory.model';
@@ -83,6 +85,7 @@ interface JoinPluginConsentDialog {
   ],
   viewProviders: [
     provideIcons({
+      lucideArrowLeft,
       lucideExternalLink,
       lucideFileText,
       lucideSearch,
@@ -110,14 +113,22 @@ export class ServerSearchComponent implements OnInit {
   private webrtc = inject(RealtimeSessionFacade);
   private pluginRequirements = inject(PluginRequirementService);
   private pluginStore = inject(PluginStoreService);
+  private viewport = inject(ViewportService);
   private searchSubject = new Subject<string>();
   private banLookupRequestVersion = 0;
 
+  /** True on mobile breakpoints. Drives the tabbed mobile layout. */
+  readonly isMobile = this.viewport.isMobile;
+
+  /** Active mobile tab. Ignored on desktop where both panes are visible side-by-side. */
+  readonly mobileTab = signal<'people' | 'servers'>('servers');
+
   searchQuery = '';
   searchResults = this.store.selectSignal(selectSearchResults);
   isSearching = this.store.selectSignal(selectIsSearching);
   error = this.store.selectSignal(selectRoomsError);
   savedRooms = this.store.selectSignal(selectSavedRooms);
+  currentRoom = this.store.selectSignal(selectCurrentRoom);
   currentUser = this.store.selectSignal(selectCurrentUser);
   activeEndpoints = this.serverDirectory.activeServers;
   bannedServerLookup = signal<Record<string, boolean>>({});
@@ -235,6 +246,24 @@ export class ServerSearchComponent implements OnInit {
     this.settingsModal.open('network');
   }
 
+  /**
+   * Navigate back from the Search page to the chat-room view (server rail + current server).
+   * Prefers the current room; falls back to the first saved room. No-op when the user has not
+   * joined any servers.
+   */
+  goBack(): void {
+    const target = this.currentRoom() ?? this.savedRooms()[0] ?? null;
+
+    if (target) {
+      this.store.dispatch(RoomsActions.viewServer({ room: target }));
+    }
+  }
+
+  /** True when the back button has a destination (user is in or has joined at least one server). */
+  canGoBack(): boolean {
+    return !!this.currentRoom() || this.savedRooms().length > 0;
+  }
+
   /** Join a previously saved room by converting it to a ServerInfo payload. */
   joinSavedRoom(room: Room): void {
     this.openJoinedRoom(room);