Add functionality to edit sheets with save and restore

lib/edit_bottom_sheet.dart

@@ -0,0 +1,70 @@
+import 'package:flutter/material.dart';
+import 'package:sheetless/sheet.dart';
+
+typedef SheetEditedCallback = void Function(String newName, String newComposer);
+
+class EditItemBottomSheet extends StatefulWidget {
+  final Sheet sheet;
+  final SheetEditedCallback onSheetEdited;
+
+  const EditItemBottomSheet({
+    super.key,
+    required this.sheet,
+    required this.onSheetEdited,
+  });
+
+  @override
+  State<EditItemBottomSheet> createState() => _EditItemBottomSheetState();
+}
+
+class _EditItemBottomSheetState extends State<EditItemBottomSheet> {
+  late TextEditingController sheetNameController;
+  late TextEditingController composerNameController;
+
+  @override
+  void initState() {
+    sheetNameController = TextEditingController(text: widget.sheet.name);
+    composerNameController = TextEditingController(
+      text: widget.sheet.composerName,
+    );
+    super.initState();
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    return Padding(
+      padding: EdgeInsets.fromLTRB(
+        16,
+        16,
+        16,
+        MediaQuery.of(context).viewInsets.bottom + 16,
+      ),
+      child: Column(
+        mainAxisSize: MainAxisSize.min,
+        children: [
+          TextField(
+            controller: sheetNameController,
+            decoration: InputDecoration(labelText: "Sheet"),
+          ),
+          TextField(
+            controller: composerNameController,
+            decoration: InputDecoration(labelText: "Composer"),
+          ),
+          const SizedBox(height: 16),
+          ElevatedButton(
+            onPressed: () {
+              // TODO: check text fields are not empty
+              // TODO: save on pressing enter
+              widget.onSheetEdited(
+                sheetNameController.text,
+                composerNameController.text,
+              );
+              Navigator.pop(context);
+            },
+            child: Text("Save"),
+          ),
+        ],
+      ),
+    );
+  }
+}