feat(12-02): replace config-page library section with full library management UI

- Add library list with name, path, track count per library
- Add Library button opens folder picker, auto-creates library
- Inline rename with Enter/Escape via overflow menu
- Removal confirmation dialog with real impact counts (tracks, playlists, queue)
- Toast notification with removal summary after library removal
- Add GetAllLibrariesWithTrackCounts + Info type to backend Library struct
- Add Wails binding stubs for AddLibrary, RenameLibrary, RemoveLibrary, GetRemovalImpact
- Add Info, RemovalImpact, RemovalSummary types to models.ts
- Remove old single-directory library config UI (GetLibraryDirectory/SetLibraryDirectory)

frontend/wailsjs/go/library/Library.js

@@ -2,6 +2,10 @@
 // Cynhyrchwyd y ffeil hon yn awtomatig. PEIDIWCH Â MODIWL
 // This file is automatically generated. DO NOT EDIT
 
+export function AddLibrary(arg1) {
+  return window['go']['library']['Library']['AddLibrary'](arg1);
+}
+
 export function CancelAllScans() {
   return window['go']['library']['Library']['CancelAllScans']();
 }
@@ -22,6 +26,10 @@ export function GetAlbumTracks(arg1) {
   return window['go']['library']['Library']['GetAlbumTracks'](arg1);
 }
 
+export function GetAllLibrariesWithTrackCounts() {
+  return window['go']['library']['Library']['GetAllLibrariesWithTrackCounts']();
+}
+
 export function GetAlbumsByArtist(arg1) {
   return window['go']['library']['Library']['GetAlbumsByArtist'](arg1);
 }
@@ -42,6 +50,10 @@ export function GetAllTracks() {
   return window['go']['library']['Library']['GetAllTracks']();
 }
 
+export function GetRemovalImpact(arg1) {
+  return window['go']['library']['Library']['GetRemovalImpact'](arg1);
+}
+
 export function GetScanQueueLength() {
   return window['go']['library']['Library']['GetScanQueueLength']();
 }
@@ -62,6 +74,14 @@ export function PauseScan() {
   return window['go']['library']['Library']['PauseScan']();
 }
 
+export function RemoveLibrary(arg1) {
+  return window['go']['library']['Library']['RemoveLibrary'](arg1);
+}
+
+export function RenameLibrary(arg1, arg2) {
+  return window['go']['library']['Library']['RenameLibrary'](arg1, arg2);
+}
+
 export function QueuedLibraryNames() {
   return window['go']['library']['Library']['QueuedLibraryNames']();
 }