feat(ts): add typescript declaration file

Author: LonelyCpp

index.d.ts

@@ -0,0 +1,21 @@
+declare const RNBiometrics: {
+  /**
+   * request biometric authentication
+   *
+   * note: promise will resolve when successful
+   * but will be rejected when not with an error message
+   */
+  requestBioAuth: (
+    /** title of prompt (can be an empty string) */
+    promptTitle: string,
+    /** The app-provided reason for requesting authentication, which displays in the authentication dialog presented to the user. */
+    promptMessage: string
+  ) => Promise<boolean>;
+
+  /**
+   * check if authentication is possible
+   */
+  canAuthenticate: () => Promise<boolean>;
+};
+
+export default RNBiometrics;

index.js

@@ -1,4 +1,4 @@
-import { NativeModules, Platform } from "react-native";
+import { NativeModules } from "react-native";
 
 const { RNBiometrics: RNBiometricsNative } = NativeModules;