perf(context): improve initializing Context

[yusukebe]

This PR improves the performance for initialization of Context:

• Delay initialization for variables as long as possible.
• Pass Request object instead of HonoRequest and make it later if c.req is called.
• Some tests have been changed. But I think it is not a problem because Context is used in the hono package internally, though a type of Context is exported.
• It's not related to performance, but use # for some private properties.

Result

With this benchmark code:

import { bench, group, run } from 'mitata'
import { Hono as HonoNext } from '../../dist/index.js'
import { Hono } from 'hono'

const req = new Request('http://localhost/')
const app = new Hono().get('/', (c) => c.text('Hi'))
const appNext = new HonoNext().get('/', (c) => c.text('Hi'))

bench('noop', () => {})

group(() => {
  bench('4.4.8', async () => {
    await app.fetch(req)
  })
  bench('next', async () => {
    await appNext.fetch(req)
  })
})

run()

The performance is improved.

Bun:

benchmark      time (avg)             (min … max)       p75       p99      p999
------------------------------------------------- -----------------------------
4.4.8         906 ns/iter     (850 ns … 1'490 ns)    892 ns  1'303 ns  1'490 ns
next          821 ns/iter     (772 ns … 1'145 ns)    822 ns  1'094 ns  1'145 ns

summary
  next
   1.1x faster than 4.4.8

Node.js:

benchmark      time (avg)             (min … max)       p75       p99      p999
------------------------------------------------- -----------------------------
4.4.8       1'099 ns/iter   (1'012 ns … 2'116 ns)  1'101 ns  1'715 ns  2'116 ns
next        1'055 ns/iter     (987 ns … 1'317 ns)  1'075 ns  1'274 ns  1'317 ns

summary
  next
   1.04x faster than 4.4.8

The author should do the following, if applicable

• Add tests
• Run tests
• bun run format:fix && bun run lint:fix to format the code
• Add TSDoc/JSDoc to document the code

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 95.84%. Comparing base (d21f8eb) to head (b62a687).

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #3046   +/-   ##
=======================================
  Coverage   95.83%   95.84%           
=======================================
  Files         137      137           
  Lines       13398    13423   +25     
  Branches     2258     2292   +34     
=======================================
+ Hits        12840    12865   +25     
  Misses        558      558           

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[yusukebe]

Hey @usualoma !

What do you think of this?

[usualoma]

@yusukebe
Great! Let’s go with this.

[EdamAme-x]

looks faster!

------------------------------------------------- -----------------------------
4.4.8       1'890 ns/iter   (1'656 ns … 4'385 ns)  1'768 ns  4'319 ns  4'385 ns
next        1'563 ns/iter   (1'435 ns … 2'181 ns)  1'566 ns  2'167 ns  2'181 ns

summary
  next
   1.21x faster than 4.4.8

[yusukebe]

@usualoma @EdamAme-x Thanks! I'll merge this into the main now.