docs: Add TSDoc comments to improve code documentation and readability

[fzn0x]

This PR will takes a long time, I wouldn't finish it in a day.

But this is a good start, anyone can contribute in my repository https://github.com/fzn0x/hono/tree/fzn0x/tsdoc

The author should do the following, if applicable

• [ ] Add tests
• [ ] Run tests
• [ ] bun denoify to generate files for Deno
• [ ] bun run format:fix && bun run lint:fix to format the code

[fzn0x]

This will close https://github.com/honojs/hono/issues/1338

[fzn0x]

https://hono.dev/api/request

TODO: add blob() and formData()

[fzn0x]

https://github.com/honojs/hono/pull/2677/commits/56f1e1f703873d63c212afdcd32270e2b9b8e582 TSDoc comments are generally not as necessary in file that only contains modules export, but for completeness, it should be necessary

[yusukebe]

@fzn0x

mod.ts, middleware.ts, and help.ts will be remove in #2662

[fzn0x]

Okay, lets skip those files @yusukebe

[fzn0x]

src/*.ts tsdoc is done, i will continue with src/adapter

[fzn0x]

I will continue this on weekend, have a lot of works recently, can't spend my time for open source make me sad

[yusukebe]

Hi @fzn0x

I've merged other PRs to the next. I'll release the RC version for v4.4. And will release v4.4.0 in the next week.

I'd like to use the documents you wrote in this PR, but you don't need to hurry. It can be merged after releasing the v4.4.0.

And, we have to refer to the JSDoc format that @goisaki wrote in the PRs #2680.

[yusukebe]

Hey @fzn0x

For now, shall we merge the current PR which added docs to src/*.ts?

[yusukebe]

@fzn0x

I'll release v4.4.0 today. This PR is good, but it differs widely from the current next branch. So, after releasing v4.4.0, let's update and merge!

[fzn0x]

Hi @yusukebe sure, lets do it :)