add typings

[Drapegnik]

Hi! 👋

Firstly, thanks for your work on this project! 🙂

Today I used patch-package to patch http-range-parse@1.0.0 for the project I'm working on.

Here is the diff that solved my problem:

diff --git a/node_modules/http-range-parse/index.d.ts b/node_modules/http-range-parse/index.d.ts
new file mode 100644
index 0000000..7ef8f87
--- /dev/null
+++ b/node_modules/http-range-parse/index.d.ts
@@ -0,0 +1,18 @@
+declare module 'http-range-parse' {
+  declare interface Range {
+    first: number;
+    last: number;
+  }
+
+  declare function parse(
+    str: string
+  ): {
+    unit?: string;
+    first?: number;
+    last?: number;
+    suffix?: number;
+    ranges?: Range[];
+  };
+
+  export default parse;
+}

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