fix: update cn function type and import cx from tailwind-variants/lite (#285)

- Change the type of cn function to allow callable string representation.
- Update import statement in MIGRATION-V3.md to use cx instead of cnBase.

Author: jrgarciadev

MIGRATION-V3.md

@@ -33,5 +33,5 @@ pnpm add tailwind-merge
 If you do not need conflict resolution, switch to the lite build by importing from `tailwind-variants/lite`:
 
 ```ts
-import {createTV, tv, cn, cnBase} from "tailwind-variants/lite";
+import {createTV, tv, cn, cx} from "tailwind-variants/lite";
 ```

src/index.d.ts

@@ -21,6 +21,16 @@ export type * from "./types.d.ts";
  */
 export declare const cx: <T extends CnOptions>(...classes: T) => CnReturn;
 
+/**
+ * Type representing a callable function that can also be coerced to a string.
+ * This allows `cn` to work both as a function and directly in template literals.
+ */
+type CnCallable = ((config?: TWMConfig) => CnReturn) & {
+  toString(): string;
+  valueOf(): CnReturn;
+  [Symbol.toPrimitive](hint: "string" | "number" | "default"): string | CnReturn;
+} & string;
+
 /**
  * Combines class names and merges conflicting Tailwind CSS classes using `tailwind-merge`.
  * @param classes - Class names to combine (strings, arrays, objects, etc.)
@@ -39,7 +49,7 @@ export declare const cx: <T extends CnOptions>(...classes: T) => CnReturn;
  * // Use: cx('bg-red-500', 'bg-blue-500') // => 'bg-red-500 bg-blue-500'
  * ```
  */
-export declare const cn: <T extends CnOptions>(...classes: T) => (config?: TWMConfig) => CnReturn;
+export declare const cn: <T extends CnOptions>(...classes: T) => CnCallable;
 
 /**
  * Creates a variant-aware component function with Tailwind CSS classes.