docs(codec): avoid repeating type declare

[homura]

This PR guides users on how to define TS types in a simple way when using the @ckb-lumos/codec

import { molecule } from "@ckb-lumos/codec";
import type { UnpackResult } from "@ckb-lumos/codec";
const { struct } = molecule;

const RGB = struct(
  { r: Uint8, g: Uint8, b: Uint8 },
  ["r", "g", "b"] 
);

// We don't need to repeat the definition like this
// type UnpackedRGB = { r: number; g: number; b: number };
type UnpackedRGB = UnpackResult<typeof RGB>;

[vercel]

The latest updates on your projects. Learn more about Vercel for Git ↗︎

Name	Status	Preview	Updated
lumos-website	✅ Ready (Inspect)	Visit Preview	Jun 23, 2022 at 6:45AM (UTC)

[codecov]

Codecov Report

Merging #359 (1de99e3) into develop (0c57197) will increase coverage by 0.07%.
The diff coverage is n/a.

@@             Coverage Diff             @@
##           develop     #359      +/-   ##
===========================================
+ Coverage    78.40%   78.48%   +0.07%     
===========================================
  Files           83       83              
  Lines        20224    20248      +24     
  Branches      1827     1847      +20     
===========================================
+ Hits         15856    15891      +35     
+ Misses        4347     4336      -11     
  Partials        21       21              

Impacted Files	Coverage Δ
packages/debugger/src/types.ts	100.00% <0.00%> (ø)
packages/debugger/src/executor.ts	100.00% <0.00%> (ø)
packages/debugger/src/context.ts	89.39% <0.00%> (+0.75%)	⬆️
packages/debugger/src/parse.ts	100.00% <0.00%> (+3.29%)	⬆️
packages/debugger/src/download.ts	96.55% <0.00%> (+12.91%)	⬆️

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 0c57197...1de99e3. Read the comment docs.

[zhangyouxin]

LGTM