fix(factory): relax Bindings and Variables for createMiddleware

[yusukebe]

If there were type mismatches regarding Bindings and Variables with nested middleware created by createMiddleware, it threw the error. I've fixed it does not throw the type error.

type Bindings = {
  MY_VAR_IN_BINDINGS: string
}

const app = new Hono<{ Bindings: Bindings }>()

type Variables = {
  MY_VAR: string
}
const middleware = (_variable: string) =>
  createMiddleware<{ Variables: Variables }>(async (c, next) => {
    await next()
  })

app.get(
  '/',
  createMiddleware<{ Bindings: Bindings }>(async (c, next) => {
    const mw = middleware(c.env.MY_VAR_IN_BINDINGS)
    await mw(c, next) // `c` does not throw an error
  }),
  (c) => {
    return c.json({})
  }
)

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 95.58%. Comparing base (31b4cd4) to head (f2e0059).
Report is 1 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #3498   +/-   ##
=======================================
  Coverage   95.58%   95.58%           
=======================================
  Files         155      155           
  Lines        9357     9357           
  Branches     2730     2764   +34     
=======================================
  Hits         8944     8944           
  Misses        413      413           

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.