fix(12-02): replace removed Scan() import with ScanAllLibraries()

Scan() wrapper was deleted in Phase 11 but config-page.ts and
library-manager.ts still imported it. Use ScanAllLibraries() for
soft scan since multi-library model scans all libraries.

frontend/src/components/config-page/config-page.ts

@@ -3,7 +3,6 @@ import { customElement, state } from 'lit/decorators.js';
 import { repeat } from 'lit/directives/repeat.js';
 import { EventsOn } from '@runtime/runtime';
 import {
-    Scan,
     FullRescan,
     CancelCurrentScan,
     CancelAllScans,
@@ -1427,7 +1426,7 @@ export class ConfigPage extends LitElement {
 
     private handleSoftScan = async (): Promise<void> => {
         try {
-            await Scan();
+            await ScanAllLibraries();
         } catch (err) {
             this.statusMessage =
                 'Scan completed with errors.';

frontend/src/components/library-manager/library-manager.ts

@@ -2,7 +2,6 @@ import { LitElement, html, css, nothing } from 'lit';
 import { customElement, state } from 'lit/decorators.js';
 import { EventsOn } from '@runtime/runtime';
 import {
-    Scan,
     FullRescan,
     ScanAllLibraries,
 } from '@go/library/Library';
@@ -812,7 +811,7 @@ export class LibraryManager extends LitElement {
 
     private handleSoftScan = async (): Promise<void> => {
         try {
-            await Scan();
+            await ScanAllLibraries();
         } catch (err) {
             this.statusMessage =
                 'Scan completed with errors.';