Certainly！I’ll provide an explanation for each line or block of code inside a comment：

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// 1-3. Importing necessary hooks and utilities from React, the nanoid library for generating unique IDs, and various components and utilities from the @raycast/api package.
import { useCallback, useEffect, useState } from "react";
import { nanoid } from "nanoid";
import { ActionPanel, Icon, List, LocalStorage } from "@raycast/api";

// 4-5. Importing TypeScript types for Filter and Todo from another file.
import { Filter, Todo } from "./types";

// 6-10. Importing custom components specific to the todo application.
import { CreateTodoAction, DeleteTodoAction, EmptyView, ToggleTodoAction } from "./components";

// 12-18. Defining the shape of the component's state using TypeScript interface.
type State = {
  filter: Filter;
  isLoading: boolean;
  searchText: string;
  todos: Todo[];
  visibleTodos: Todo[];
};

// 20-21. The main functional component for the todo command.
export default function Command() {
  // 22-30. Initializing the component's state with default values.
  const [state, setState] = useState<State>({
    filter: Filter.All,
    isLoading: true,
    searchText: "",
    todos: [],
    visibleTodos: [],
  });

  // 32-47. Fetching and setting todos from local storage on component mount.
  useEffect(() => {
    (async () => {
      const storedTodos = await LocalStorage.getItem<string>("todos");

      if (!storedTodos) {
        setState((previous) => ({ ...previous, isLoading: false }));
        return;
      }

      try {
        const todos: Todo[] = JSON.parse(storedTodos);
        setState((previous) => ({ ...previous, todos, isLoading: false }));
      } catch (e) {
        // Handling errors if the stored data can't be parsed.
        setState((previous) => ({ ...previous, todos: [], isLoading: false }));
      }
    })();
  }, []);

  // 49-52. Effect hook to store todos in LocalStorage whenever the todos state changes.
  useEffect(() => {
    LocalStorage.setItem("todos", JSON.stringify(state.todos));
  }, [state.todos]);

  // 54-61. Callback for creating a new todo.
  const handleCreate = useCallback(
    (title: string) => {
      const newTodos = [...state.todos, { id: nanoid(), title, isCompleted: false }];
      setState((previous) => ({ ...previous, todos: newTodos, filter: Filter.All, searchText: "" }));
    },
    [state.todos, setState]
  );

  // 63-70. Callback to toggle the completion status of a todo.
  const handleToggle = useCallback(
    (index: number) => {
      const newTodos = [...state.todos];
      newTodos[index].isCompleted = !newTodos[index].isCompleted;
      setState((previous) => ({ ...previous, todos: newTodos }));
    },
    [state.todos, setState]
  );

  // 72-79. Callback for deleting a todo.
  const handleDelete = useCallback(
    (index: number) => {
      const newTodos = [...state.todos];
      newTodos.splice(index, 1);
      setState((previous) => ({ ...previous, todos: newTodos }));
    },
    [state.todos, setState]
  );

  // 81-90. Callback to filter todos based on the current filter state.
  const filterTodos = useCallback(() => {
    if (state.filter === Filter.Open) {
      return state.todos.filter((todo) => !todo.isCompleted);
    }
    if (state.filter === Filter.Completed) {
      return state.todos.filter((todo) => todo.isCompleted);
    }
    return state.todos;
  }, [state.todos, state.filter]);

  // 92-127. Defines the UI structure using JSX.
  return (
    <List
      isLoading={state.isLoading}
      searchText={state.searchText}
      searchBarAccessory={
        <List.Dropdown
          tooltip="Select Todo List"
          value={state.filter}
          onChange={(newValue) => setState((previous) => ({ ...previous, filter: newValue as Filter }))}
        >
          <List.Dropdown.Item title="All" value={Filter.All} />
          <List.Dropdown.Item title="Open" value={Filter.Open} />
          <List.Dropdown.Item title="Completed" value={Filter.Completed} />
        </List.Dropdown>
      }
      enableFiltering
      onSearchTextChange={(newValue) => {
        setState((previous) => ({ ...previous, searchText: newValue }));
      }}
    >
      <EmptyView filter={state.filter} todos={filterTodos()} searchText={state.searchText} onCreate={handleCreate} />
      {filterTodos().map((todo, index) => (
        <List.Item